Common ESL Writing Errors
  • 51-minute read
  • 29th January 2021

Common ESL Writing Errors

Learning English can be hard work! It is, at best, a complicated language with many rules and almost as many exceptions to those rules. As such, at Proofed, we have nothing but respect for English as a second language (ESL) – also known as English as an additional language (EAL) or English for speakers of other languages (ESOL) – learners.

Luckily, our editors have a lot of experience working with ESL customers. This means we’re good at spotting the kinds of errors that many ESL writers make. And to help out, we’ve compiled this list of 15 common ESL errors and how to fix them.

Article Usage

Articles are a kind of determiner (i.e., short words we place before nouns to tell us something about them). In English, we have two article types: definite (the) and indefinite (a or an). In the following, we’ll look at some common errors related to article usage and how to fix them.

Definite Or Indefinite Article?

ESL writers sometimes mix up the definite and indefinite articles. But each of these has a specific use, so using the wrong one can create problems. Remember:

  • We use the definite article (the) when we know the specific identity of a noun. This could be because it is unique (e.g., the President of the USA), a superlative (e.g., the tallest man), or because its identity is clear from the context (e.g., if I say I am going to “walk the dog,” you can guess I have a specific dog in mind).

Using the wrong article type won’t necessarily make your writing ungrammatical, but it can change the meaning of what you say. For example:

I need to see a doctor! = I need to see any doctor who is available.
I need to see the doctor! = I need to see a specific doctor.

As such, you should be careful about article choice when writing. And, in general, if you are definite about the identity of the noun, you will need the definite article (i.e., “the”).

Article Omission And The Zero Article

If you are using a concrete, singular countable noun or a superlative, it will need an article or another determiner before it. Leaving out the article will be ungrammatical:

My brother is pilot.
My sister is fastest runner.
My brother is a pilot.
My sister is the fastest runner.

However, you should use a noun without an article in some cases. This is sometimes known as the zero article, and we’ll look at where it applies in the following sections.

Plural And Uncountable Nouns

You do not need an article with plural, uncountable, or abstract nouns when making generalizations or referring to a whole class of things, such as in the following:

The cars drive on roads.
Everyone deserves the happiness.
Cars drive on roads.
Everyone deserves happiness.

Here, using articles in the first sentences makes them too specific. “The cars” implies that we’re talking about a specific group of cars rather than cars in general. And “the happiness” is simply wrong, since “happiness” is an abstract, indivisible concept. As such, we’ve removed the articles in the second set of sentences to make them grammatical.

Proper Nouns

We do not typically use articles before proper nouns, including the names of people, countries, languages, places, months, individual landmarks, etc.

We are going to the France.
I speak the English.
We are going to France.
I speak English.

There are some exceptions to this, such as when referring to:

  • A specific day (e.g., We went out the Friday before last)
  • A group of places (e.g., We live in the United States)
  • A place with an article in its name (e.g., the Eiffel Tower, the Matterhorn)

However, the zero article will be correct for most proper nouns.

Meals, Substances, Games, And Places

In some cases, we can use singular countable nouns in a general sense without an article. Common examples of this include meals, substances, games, and places:

We are going out for dinner.
It is made of gold.
We are playing chess.
I am going to school.

These are all correct! The key is that the noun is used to refer to a general concept in each case (e.g., we are referring to gold in general, not a specific piece of gold). We can use articles with these words sometimes, too, but only if referring to something specific.

For instance, if we said “We had a great dinner at that restaurant,” using “a” would show that we’re referring to one specific dinner, not the general concept of dinner.

A Or An?

Another very common error we see in ESL writing is mixing up “a” and “an.” These are both indefinite articles, so they play the same grammatical role. But the correct term to use in any given sentence will depend on the pronunciation of the noun that follows:

  • If it starts with a consonant sound, use “a” (e.g., a puppy).
  • If it begins with a vowel sound, use “an” (e.g., an egg).

Keep in mind that this applies to the sound of the word, not the letter itself. As such, you should use “a” with words like “university” or “European” as they start with a “y” sound. And you should use “an” with “hour” and “honor” as the “h” at the start of these words is silent.

Mixing Articles And Possessive Pronouns

As mentioned, articles are a type of determiner. Possessive pronouns (e.g., my, your, his, her, its, our, their) are also determiners, telling us who a noun belongs to. These words thus play a similar grammatical role to articles, so you do not need both:

Have you seen my glasses?

Here, for instance, “my” and “the” both modify “glasses.” But since “my” already suggests specificity (i.e., they are my glasses, not just any glasses), we don’t need “the.”

Problem Prepositions

Prepositions are crucial linking words in English, showing us the relationship between different parts of a sentence. However, there are many prepositions in English and some of them overlap in meaning, so it is easy to use them incorrectly or get them mixed up.

In this section, then, we’ll look at some common preposition errors.

Missing Prepositions And Intransitive Verbs

An intransitive verb is a verb that does not need an object (i.e., the thing to which an action happens) to make sense. As such, if you try to add a noun or noun phrase after an intransitive verb as an object, the sentence will be ungrammatical. The verb “spoke,” for instance, is intransitive, so the following is incorrect:

I spoke my brother.

If we wanted to show the relationship between “I spoke” and “my brother” here, we would need a preposition to link the intransitive verb to its object:

I spoke to my brother.

Here, for instance, the preposition “to” shows us the speaker and their brother have spoken. It can therefore help to check whether a verb is transitive or intransitive, as this will tell you whether or not the sentence needs an object.

Unnecessary Prepositions And Transitive Verbs

We can also flip the issue above and focus on transitive verbs. These always take a direct object, so you do not need a preposition between verb and object:

We discussed the weather.

Here, for instance, the transitive verb “discussed” is followed by the noun phrase “the weather” (i.e., the subject of the discussion). This is completely grammatical as it is. However, some ESL writers will add a preposition after an intransitive verb:

We discussed about the weather.

This is not necessary or grammatical. It results from treating a transitive verb as if it were intransitive. As above, then, if you’re not sure whether to use a prepositional phrase after a verb, it can help to check whether the verb is transitive or intransitive. Remember:

  • Transitive verb = No preposition required between verb and object.

  • Intransitive verb = Needs a preposition between verb and object.

Preposition Choice And Incorrect Prepositions

There are a lot of prepositions in English and most of them have more than one meaning. As such, we won’t try to define them all here. But we will look at how preposition choice can affect the meaning of a sentence, followed by a range of commonly confused prepositions.

In terms of how preposition choice affects the meaning of a sentence, we can show this by returning to one of the examples above that used the preposition “to”:

I spoke to my brother.

The “to” here shows that the speaker is having a discussion with their brother. But if we use a different preposition in the same place, the relationship changes:

I spoke about my brother.

Here, the preposition “about” indicates that “my brother” is the subject of the discussion: i.e., the person the speaker is talking about, not the person to whom they are speaking. So while both sentences are grammatical, they are very different in meaning.

As such, you need to make sure not just that a sentence contains a preposition when it needs one, but that you use the right prepositions in the right places! We’ll now take a look at a few examples of commonly confused prepositions to help you do this.

Times Of Day (In Vs. At)

With “in” and “at,” the correct term may depend on the time of day! For example, in English we typically use “in the” with “morning,” “afternoon,” and “evening”:

Helen goes running in the morning.
Tim goes running in the afternoon.
Shirley goes running in the evening.

But we usually use “at” when talking about the night:

Bob goes running at night.

You could go for a run “in the night,” but that sounds like something a sporty vampire would do. So make sure to use “at” with “night” in your writing.

Arrivals (In Vs. At Vs. To)

You can use the preposition “to” to discuss journeys (e.g., “I’m going to Tasmania”). But with the word “arrive,” we use “in” or “at” to describe reaching a destination. For instance:

She arrived in Tasmania just after lunch.
He arrived at the restaurant five minutes late.

Whether to use “in” or “at” typically depends on the destination:

  • Use “in” for cities, countries, or other large areas.
  • Use “at” for specific places (e.g., a library, a bar, or someone’s house).

Make sure to consider the destination when picking a preposition to go with “arrive.”

Time, Days, Months, And Years (At, On, And In)

When referring to a time or date, we use different prepositions depending on the situation. If you’re talking about a time of day, for instance, the correct term is “at”:

The party starts at 9pm.

For a specific day or date, we use “on”:

The party is on Saturday.

And for a month or year, the correct preposition is “in”:

We’re having a party in April.

In other words, the preposition depends on the time window in question.

Should Of Vs. Should Have

It’s common to see “of” used alongside helper verbs like “should” or “must.” For example:

I should of gone to bed earlier.

However, the correct word here isn’t even a preposition. It should be the verb “have,” which sounds a bit like “of” when spoken (hence the confusion). Thus, it should say:

I should have gone to bed earlier.

So if you find yourself using “of” after a helper verb, the correct word will usually be “have”.

Waiting (For Vs. Since)

When talking about how long something has been happening, we use “for” when referring to a length of time (e.g., a period of hours, days, or months):

I’ve been writing for six hours.

But if we’re using a specific time as a point of reference, we use “since”:

I’ve been writing since breakfast.

The difference here is that the first sentence refers to a measure of time, while the second refers to a fixed point in the past when the activity began.

Media (In Vs. On)

We can use the prepositions “in” and “on” to describe the medium via which we see or hear something. However, we tend to use “in” only with print media:

I read it in a newspaper article.
I read it in a newspaper article.
I read it in a book.

And we use “on” when referring to broadcast or digital media:

I saw it on television.
I heard it on the radio.
I read it on the internet.

As such, make sure to pick the preposition that matches the media you’re discussing.

This is not a complete list of preposition errors! Hopefully, though, it has given you a sense of how prepositions work and what to look for in your own writing. And don’t forget to ask a native speaker or a proofreader if you’re unsure about your preposition choices.

Word Order

In a grammatical sentence, all the parts have to be in the correct order. Using an incorrect word order, on the other hand, may lead to errors or a lack of clarity. Thankfully, the basics of word order are easy to remember if you use the initialism “SVO.”

Subject + Verb + Object (SVO)

The basic word order in English is captured in the initials SVO:

Subject + Verb + Object

Each of these plays a specific role in the sentence:

  • Subject (S) – The person or thing that enacts the verb in the sentence.
  • Verb (V) – The action or state of being described.
  • Object (O) – The direct object is the person or thing being acted upon.

The minimum required for a grammatical sentence is a subject (i.e., the person or thing doing or being something) followed by a verb (i.e., the action or state of being):

Subject (S)
Verb (V)

The sentence above has only two words: The proper noun “Steve” and the verb “dances.” This is a grammatical sentence, but only if we use those words in the order shown. If we were to reverse the word order here (i.e., “Dances Steve”), it would not make sense.

Any sentence with a transitive verb will also require a direct object after the verb. This “object” is the thing being acted upon in the sentence. For example:

Subject (S)
Verb (V)
Object (O)
the ball.

In the sentence above, the subject (“Sally”) acts upon (“kicks”) the object (“the ball”). Any order other than SVO here would be ungrammatical without adding extra words. As such, this basic word order is often the clearest, most concise option available.

Indirect Objects

An indirect object receives the direct object in a sentence, such as in the following:

Direct Object
the present
his grandad.

To break this down a bit, in this case:

  • “Jimmy” is the subject.
  • The verb is “gave.”
  • The direct object is “the present.”
  • And “his grandad” is the indirect object.

As you can see, then, following a preposition like “to” or “for,” we place the indirect object after the object. However, if we omit the preposition from the sentence, the indirect object would go before the object (making the correct order subject + verb + indirect object + object):

Indirect Object
his grandad
Direct Object
the present.

This distinction is key, so it’s always worth checking whether your sentence contains a preposition if you’re unsure about the correct word order.

Common Spelling Errors

English spelling is famously difficult. We have a lot of words borrowed from various places, many of which aren’t spelled the way they sound. As such, it can be hard to avoid spelling errors in your writing. General tips for good spelling include:

  • Practicing words you find difficult or problematic.
  • Having access to a good dictionary.
  • Setting the spell-checking tool in your word processor to the correct dialect for your document (e.g., American English, British English, or Australian English).
  • Asking a native English speaker or proofreader to check your work.

However, we will also look at some common errors and spelling rules below.

Letter Omission And Addition

Letter omission and letter addition are common causes of spelling errors:

  • Omitting a letter means missing it from a word.
  • Letter addition means adding an unnecessary letter to a word.

There is no simple rule for spotting these errors, but they are especially common in words that contain double letters. In some cases, people miss a double letter from a word:

Correct Spelling

Incorrect Spelling


In other cases, people may add a second double letter to a word that only needs one:

Correct Spelling

Incorrect Spelling


As such, make sure to double check any word with a double letter that you’re unsure about.

Silent Letters

Silent letters are just what they sound like: letters or letter combinations that are part of how a word is spelled, but which aren’t pronounced when a word is spoken.

Take the word “gnome,” for example. The “g” at the start of this word is silent, so it’s pronounced as if it were spelled “nome.” We see the same in words like “gnaw” and “sign.”

There are no strict rules in English about when a letter is silent. You can, however, learn some common silent letter combinations so that you know what to look for:

  • B after M or before T (e.g., doubt or crumb)
  • C after S in some words (e.g., scissors or ascent)
  • G before N (e.g., gnat or foreign)
  • K before N (e.g., knee or knowledge)
  • N after M (e.g., hymn or column)
  • P before S, T, or N (e.g., psychic, receipt, or pneumonia)
  • T before S in the middle of a word (e.g., castle or listen)
  • W before R or sometimes after S (e.g., write or sword)

Keep in mind that these letter combinations aren’t always silent. This is particularly true when the two letters are part of different syllables, such as in the word “magnet.”

There are also cases that don’t follow any obvious pattern. For example, while the “c” after the “s” is silent in a word like “muscle,” it is pronounced in words like “score” and “disc.” This makes silent letters tricky to master, but practicing difficult words will definitely help!

Spelling Rules: I Before E Except After C

The phrase “i before e except after c” reminds us that “i” comes before “e” in many words, except when it is preceded by a “c.” This typically applies when the “ei/ie” letter combination is pronounced as an “ee” sound, such as in the following terms:

Words Spelled “ie” (No “c”) Words Spelled with “ei” After “c”
Believe Deceive
Achieve Perceive
Diesel Ceiling
Acquiesce Receipt

“I before e except after c” can therefore be a helpful rule if you’re not sure how to spell a word. However, there are several exceptions to this rule, including:

  • Words that end “cy” when adding a suffix (e.g., “bouncy” to “bounciest”)
  • Words that don’t contain an “ee” sound (e.g., “beige” or “foreign”)

There are also a few words that contain an “ee” sound and are spelled with an “-ei-” despite it not following a “c” (e.g., “caffeine,” “weird,” and “seize”). As such, it always helps to check a dictionary if you’re not sure whether to use “ei” or “ie” in a word.

Spelling Rules: Changing Y To I

When a verb ends in a consonant followed by “-y,” we usually change the “y” to “i” or “ie” when adding a suffix or forming a plural. For example:

I have written a story!
I have written many stories

The example above shows a singular term and its plural. Other examples include:

  • Past tense verbs (hurryhurried)
  • Singular present tense verbs (trytries)
  • Comparatives (happyhappier)
  • Superlatives (happyhappiest)
  • Adverbs formed from adjectives (happyhappily)

There are exceptions here, too, though (e.g., the comparative and superlative forms of “sly” can be spelled “slyest/sliest” and “slyer/slier”), so keep your dictionary handy!

Spelling Rules: The Doubling Up Rule

The “doubling up” rule (also known as the 1:1:1 rule) states that, when adding a vowel suffix (e.g., “-ing” or “-ed”) to a single-syllable word that ends with one vowel followed by one consonant, we should double the final consonant. For example:


With longer words, we usually do the same when the final syllable is stressed. However, we don’t do it when the final syllable in a word before a suffix is unstressed:

Stressed Final Syllable


Unstressed Final Syllable


However, we do not usually double the letters “w,” “x,” or “y” in English, so single syllable words that end in a vowel plus “w,” “x” or “y” don’t require doubling the final letter when adding a vowel suffix (e.g., playplayer, snowsnowing, boxboxed).

Spelling Rules: Dropping the Letter E

Most of the time, if a word ends in “e,” you will need to drop it when adding a suffix that ends in a vowel. For instance, “dance” becomes “dancing” (not “danceing”).

Common suffixes that require dropping an “e” include:

Suffix Example Word Modified Version
-able Live Livable
-age Dote Dotage
-ed Inspire Inspired
-est Cute Cutest
-ing Note Noting
-ion Adulterate Adulteration
-ory Celebrate Celebratory
-ous Fame Famous

However, there are some exceptions to this rule:

  • Words that end in double vowels (e.g., “-ee” or “-oe”) don’t always require the final “e” to be dropped when adding a vowel suffix (e.g., shoeshoeing).
  • Do not drop the final “e” from words that end with either “-ce” or “-ge” when adding a suffix that starts with an “a” or an “o” (e.g., advantage → advantageous).

As elsewhere, then, you may want to keep a dictionary on hand in case you’re not sure whether to drop the final “e” in a word when adding a vowel suffix.

Irregular Plurals

Most English plurals are formed by adding “-s” to a noun (e.g., cat → cats, dog → dogs). As explained above in the spelling section, when a word ends in a “y,” we also change the “y” to an “-ies” when forming a plural (e.g., candy → candies, hippy hippies).

However, not all plurals follow these patterns. The ones that don’t are known as irregular plurals and can be tricky for ESL writers. Let’s look at some examples.

Words That End “-F” Or “-Fe”

When a word ends in an “-f” or “-fe,” the general rule is to replace the “-f” or “-fe” with “-ves” when forming a plural (like how “calf” becomes “calves”). Examples include:

Singular Plural
Half Halves
Life Lives
Scarf Scarves

This does not apply when a word ends in a “-ff,” so “sheriff” becomes “sheriffs” (not “sherives”). Other exceptions include “chiefs” and “beliefs.”

Words That End “-Us”

Often originating in Latin, words that end in “-us” typically take an “-i” in plural form:

Singular Plural
Abacus Abaci
Nucleus Nuclei
Hippopotamus Hippopotami

Again, there are exceptions to this rule, notably “virus” (which always becomes “viruses” in modern English). In other cases, you can use either the Latin ending or a regular plural version (e.g., “hippopotamuses” and “abacuses”). Generally, we’d recommend sticking to regular plural endings where possible, as these are usually clearer.

Words That End “-On” Or “-Um”

Other Latin-derived word endings include “-on” and “-um,” which take an “-a” when forming a traditional plural (so “criterion” becomes “criteria”). Additional examples include:

Singular Plural
Millennium Millennia
Automaton Automata
Bacterium Bacteria

As with “-us” word endings, though, you may be able to use a regular plural ending for some words. “Stadiums,” for instance, is now much more common than “stadia.”

Words That End “-Is” Or “-Ix”

Words with “-is,” “-ex,” or “-ix” endings tend to change to “-es” or “-ices” in their plural forms. For instance, “analysis” becomes “analyses” and “appendix” becomes “appendices”:

Singular Plural
Crisis Crises
Axis Axes
Vortex Vortices

Words That Change Vowel Sounds

Some words change their vowel sound as a plural, like how “foot” becomes “feet”. See also:

Singular Plural
Woman Women
Tooth Teeth
Mouse Mice

Words That Stay The Same

Some irregular plurals actually stay the same as the singular form of the word. Examples include “squid,” “sheep,” “fish,” and “species.” For instance, both “a fish” (singular) and “a shoal of fish” (plural) are correct. It’s also worth noting that uncountable nouns, like “water” or “sand,” stay the same regardless of the amount being described.

If you are unsure about the correct plural form for a word, check a dictionary.


Homophones are words that sound similar but have different meanings. As such, these terms are easy to get confused in writing, especially if you’ve only heard them spoken before.

For instance, “bear” and “bare” sound the same, but the first is a big hairy animal and the second means “naked,” so you wouldn’t want to mix them up in a document.

If you’re ever unsure about the spelling of a homophone in your work, make sure to ask a native English speaker or check a reliable dictionary for its definition.

There are too many homophones in English to cover them all here. However, we will look at some of the most commonly confused terms below. You can also find in-depth advice on a range of homophones if you check out the Word Choice posts on Proofed’s blog.


“Affect” and “effect” are related terms, but there is a key difference:

  • Affect is typically a verb meaning “change or influence.”
  • Effect is primarily a noun meaning “consequence or result.”

For instance, we could use “affect” in a sentence as follows:

Spending too long in the sun can affect your skin.

Here, “affect” refers to the act of changing something. But if we wanted to discuss the result of such an action, we would need the noun “effect” instead:

The effects of sun damage are long lasting.


“Accept” and “except” are both common words, but they differ in meaning:

  • Accept is a verb that usually means “receive willingly or admit.”
  • Except is usually a preposition or conjunction meaning “apart from or excluding.”

For instance, we could use each term as follows:

Bob accepted the package from the mail carrier.
I can resist everything except temptation.


“To” and “too” sound identical and look similar written down. They’re also very common terms in English writing. However, they play very different roles in a sentence.

To is usually a preposition. It has several meanings, including (among others) indicating direction or duration, identifying a recipient, or making comparisons.

Direction I am going to the store to buy a hat.
Duration The hat shop is open from 9am to 5pm.
Identity of recipient Give the hat to me.
Comparison I prefer Hats & Co. to Discount Hats 4 All.

It can also be used before an infinitive verb to express a purpose or give an opinion:

Purpose I’m wearing a hat to hide my bald spot.
Opinion If it is sunny outside, it is a good idea to wear a hat.

Too, meanwhile, is an adverb that can mean either “as well” or “excessively”:

I am going bald, too, so you’re not alone.
The sun is too hot for me to go out without a hat!

Another word that sounds similar to the above is “two” (i.e., the number “2”). But this term is clearly distinct in spelling, so it is easy to tell it apart from “to” and “too.”


While these terms are easy to mix up, they have very different meanings:

  • Its is a possessive pronoun (i.e., it shows that something belongs to an “it”).
  • It’s is a contraction of “it is” or “it has.”

This may seem confusing, as we often associate an apostrophe with possession. For instance, to show ownership with a regular noun, we add an apostrophe plus “s.” However, this is not the case with possessive pronouns like “its,” “his,” or “her.”

A contraction, meanwhile, will always need an apostrophe. As such, if you’re going to use “it’s” in a sentence, try writing it as “it is” or “it has” and see if it makes sense. If not, you probably need “its” instead. And remember not to use contractions in formal writing!


As above, here we have a possessive pronoun and a contraction:

  • Your is a possessive pronoun (i.e., it shows that something belongs to a “you”).
  • You’re is a contraction of “you are.”

The same rules as above apply here, too. As such, if you’re going to use “you’re” in a sentence, try writing it as “you are” to see if it makes sense. If not, it may be that you need the possessive pronoun “your” instead. And, again, make sure not to use contractions in formal writing! You will always be better off writing out “you are” in full if you need to be formal.


In this case, we have three words that sound similar but differ in meaning:

  • Their is a possessive pronoun (i.e., it shows that something belongs to a “they”).
  • They’re is a contraction of “they are.”
  • There can be an adverb or pronoun and indicates a location or position.

We would use each term in a sentence as follows:

Trees lose their leaves in the fall.
They’re going to win the game.
Not the red car. I mean the green car over there.

As with “it’s” and “you’re,” remember to avoid contractions in formal writing. In an essay, for example, you will always be better off writing “they are” than “they’re.”


This time, we have a verb, an adverb, and another contraction:

  • Were is a past tense form of the verb “be.”
  • Where is usually an adverb that indicates a location or position.
  • We’re is a contraction of “we are.”

The trickiest terms here are “were” and “we’re,” as both include forms of the verb “be.” However, as with the other contractions above, the apostrophe is a giveaway here! So if you’re not sure whether to use “we’re” in a sentence, try writing it as “we are” instead and see if it fits. If not, you probably need “were” or “where” instead.

As for when to use “were” or “was” (another past tense form of “be”), see the table below:

Present Tense Past Tense
First Person (Singular) I am... I was...
First Person (Plural) We are... We were...
Second Person (Singular and Plural) You are... You were...
Third Person (Singular) He/she/it is… He/she/it was…
Third Person (Plural) They are… They were…


“Lay” and “lie” sound different, so it is easy to tell them apart as present tense verbs:

  • Lay means “put something down or place it horizontally.”
  • Lie can mean either “recline” or “tell an untruth.”

The tricky part of these words is that “lay” is also the simple past tense of “lie” when used to mean “recline” (but not for “tell an untruth”). Try to remember the following:

Present Tense Lie (Recline) Lay (Put Down) Lie (Untruth)
Past Simple Lay Laid Lied
Past Participle Lain Laid Lied


Although these words sound similar, they play very different roles in a sentence:

  • Are is the second-person singular present tense (i.e., “You are”) and plural present tense (i.e., “We are,” “You are,” “They are,” etc.) form of the verb “be.”
  • Our is a first-person plural possessive pronoun, meaning “belonging to us.”

As long as you remember that “are” is a verb and “our” is a pronoun, though, it should be easy to avoid mixing up these terms in your writing.



As well as words that sound similar, English has plenty of synonyms (i.e., words with the same meaning as one another). Sometimes, this means you can use words interchangeably. For instance, “begin” and “start” can both be used as follows:

The test will begin at noon.
The test will start at noon.

Unfortunately, some words with similar meanings differ in how they are used. For example, the words “quick” and “fast” are both adjectives that mean “speedy.” But “quick” also implies brevity, which is not the case with “fast.” As such, a short conversation could be described as a “quick chat,” but a “fast chat” would imply talking at high speed!

This is why it’s important to check a dictionary when using synonyms, especially if it is an unfamiliar word from a thesaurus. Asking a native speaker can also help!

Relative Clauses: Which Or That?

The words “that” and “which” can both be used to introduce a relative clause (i.e., additional detail about something). However, each is used in a slightly different situation, which can be confusing for both native and non-native English speakers.

That (Restrictive Relative Clauses)

The term “that” is used when introducing a restrictive relative clause. This is a clause that restricts the meaning of the sentence, such as the following:

All the houses that we rented were infested.

In the above, the phrase “that we rented” identifies the specific houses being described (i.e., the houses that were rented, not those we didn’t rent). It is thus a “restrictive” clause and cannot be removed without changing the meaning of the sentence.

Which (Non-Restrictive Relative Clauses)

By contrast, “which” is used when introducing a non-restrictive relative clause. This is a clause that doesn’t restrict the meaning of the sentence:

All the houses, which we rented, were infested.

The “which” clause here introduces new information, but isn’t needed for the main point of the sentence (i.e., that all the houses were infested). The extra clause simply tells us that we rented “all the houses” but not which houses we’re referring to. As such, we could remove “which we rented” without changing the overall meaning of the sentence.

You’ll notice that the “which” clause is also set apart with commas. This is to show that it is bonus information, not essential to the main clause. We do the same thing when a non-restrictive relative clause appears at the end of the sentence:

I spent years living in infested buildings, which wasn’t much fun.

That or Which?

Keeping in mind the differences above, knowing whether to use “that” or “which” at any given point requires asking, “Does this clause change the meaning of my sentence?”

  • If removing it would change the meaning of the sentence, you need to use “that.” This is known as a restrictive relative clause.
  • If removing the detail doesn’t change the overall meaning of the sentence, you should use “which” and set the clause apart with commas. This is known as a non-restrictive relative clause.

American Vs. British English

The rules above are correct for American English. And you’ll be fine if you use the terms “that” and “which” like this in any English dialect. However, in British English and other similar English dialects, you can also use “which” for restrictive relative clauses.

That or Which? Example Sentence American English British English
That (Restrictive) The house that I built survived. Correct Correct
That (Non-Restrictive) The house, that I built, survived. Incorrect Incorrect
Which (Restrictive) The house which I built survived. Incorrect Correct
Which (Non-Restrictive) The house, which I built, survived. Correct Correct

Verb Form And Tense

In English, it is easy to get verb forms confused if you’re not familiar with the word in question. So to help you avoid errors in this respect, we’re going to look at some of the basics of subject–verb agreement, as well as some common errors related to verb tense.

Subject–Verb Agreement

The subject and verb in a sentence need to “agree.” This basically means “match in number,” so we use singular subjects with singular verbs and plural subjects with plural verbs.

For example, in the present tense singular, we usually add an “s” after the base verb form (e.g., sing becomes sings). If we have a plural subject, though, we use the base verb form:

Singular Subject
The bird…
Present Tense Singular Verb
Plural Subject
The birds…
Present Tense Plural Verb

And in the simple past tense, there’s usually no difference between singular and plural verbs:

Singular Subject
The birds...
Past Tense Singular Verb
Plural Subject
The birds…
Past Tense Plural Verb

This should be fairly simple to remember. But there are some cases where it is less clear whether to use a singular or plural verb. We’ll look at these below.

Compound Subjects

A “compound subject” is a subject made up of two nouns joined by a conjunction. When two subjects are joined with the coordinating conjunction “and,” we always use a plural verb:

Bob and Cheryl are going to the game.

However, when using “either/or” or “neither/nor” in a compound subject, whether to use a singular or plural verb depends on the noun nearest to the verb:

Singular: Either the girls or the boy is going to the game.
Plural: Neither the boy nor the girls are going to the game.

In the above, we use the singular “is” when the singular noun “boy” comes after “or,” but we use the plural verb “are” when the plural noun “girls” comes after the conjunction.

Parenthetical Statements

You can use a parenthetical statement extra information set apart from the main part of a sentence with brackets, dashes, or commas between a subject and a verb. However, the verb should agree with the main subject sentence regardless.

In the following, for example, we use the singular verb “goes” because the dog is only mentioned within commas, not as part of the subject of the sentence:

The man, in the company of his dog, goes for a walk.

If you’re not sure whether to use a singular or plural verb in a sentence with parenthetical information, then, try cutting it down to the main clause and see what fits best:

The man ... goes for a walk.
The man ... go for a walk.

Collective And Mass Nouns

In American English, collective nouns (i.e., nouns that refer to a group of things) typically require a singular verb. However, you can use a plural verb with a collective noun if the members of the group are acting as separate individuals:

Acting Together: The team is playing to win!
Acting Separately: The team are arguing with each other.

Here, we use the singular verb “is” to describe a team that is working together to win. But we use the plural verb “are” when the players are acting as individuals.

Mass (or “non-count”) nouns are similar, since they take singular verbs despite referring to a mass substance (e.g., “milk,” “water,” or “sand”):

The milk is going sour.
The water is flowing smoothly.
The sand stretches on for miles.

Here, it doesn’t matter how much we’re discussing, we always use the singular form.

Some Exceptions

As usual in English, there are exceptions to the rules above. The main two are:

  • The first-person “I” and the singular second-person “you” reverse the usual rules in the present tense (e.g., we say “I sing” not “I sings,” even though “I” is singular).
  • When using a past participle, the auxiliary verb (e.g., “is”/“are” or “has”/“have”) may change depending on whether the subject is singular or plural (e.g., “The boy has finished his homework” vs. “The boys have finished their homework”).

As long as you can remember these, you should be able to avoid most subject–verb agreement errors in your writing. But since sentence structure can affect the correct verb form, it also helps to ask a friend or proofreader if you’re unsure about anything.

Regular And Irregular Verbs

Most verbs are easy to understand because their simple past tense and past participle forms all end with the letters “-ed.” For instance, the verb “sail” becomes “sailed,” “bake” becomes “baked,” and “kick” becomes “kicked.” These are known as regular verbs.

As above, the “y-to-i” rule applies here, so we usually add “-ied” instead when a verb ends in “y” (e.g., “hurry” becomes “hurried”). But these are still “regular” verbs because their past tense and past participle forms follow a regular pattern

However, some verbs do not follow a pattern. These are known as “irregular verbs.” For example, the simple present tense verb “break” does not become “breaked,” but changes into “broke” (simple past tense) and “broken” (past participle). Other examples include:

Base Verb Simple Past Tense Past Participle
Cut Cut Cut
Drink Drank Drunk
Sit Sat Sat
Think Thought Thought
Write Wrote Written

As you can see, there is no real pattern to how irregular verbs behave:

  • Some change just one letter in different forms (e.g., drink > drank > drunk).
  • Others change more significantly (e.g., think > thought).
  • In some cases, the simple past tense and past participle forms are the same.
  • Some words use a different term for past tense and past participle forms.
  • Others don’t change from the base form in either case (e.g., cut).

The common term “be” is a standout irregular verb. “Be” is the infinitive form (i.e., “to be”), but usually you will need one of its many variations:

Verb Forms First Person Second Person Third Person
Singular Plural Singular Plural Singular Plural
Present Tense Am Are Are Are Is Are
Past Tense Was Were Were Were Was Were
Present Participle Being Being Being Being Being Being
Past Participle Been Been Been Been Been Been

Irregular verbs can, therefore, be a bit confusing! Our advice is to watch out for these terms when reading to learn how they’re used. Checking unusual terms in a dictionary and having your work proofread to correct any verb-based errors is also a good idea.

Verb Tense Confusions

Verb “tense” gives us a time reference for an action. At its most basic, for instance, we distinguish between something that is currently happening with something that happened in the past by changing the form of the verb (e.g., I walkI walked).

The correct tense to use will depend on what you are trying to express. However, we can summarize the tenses in English and their uses as follows:

Tense Example Usage
Simple Present She dances. Expressing something that is currently happening or something that happens regularly. Requires a simple present tense verb.
Simple Past I wrote a book last year. Expressing that an action happened in the past. Requires a simple past tense verb.
Simple Future She will dance. Expresses that something will happen in the future. Requires the modal verb “will” + a base verb.
Present Perfect I have written many books. Expresses an action that happened at an indefinite time in the past or started in the past and continues to the present. Requires the modal verb “have/has” plus a past participle.
Past Perfect She had danced this dance many times before. Expresses an action that happened before another point of reference. Requires the modal verb “had” plus a past participle.
Future Perfect I will have written the first chapter by next month. Used for actions that will end in the future. Requires “will have” plus a past participle.
Present Continuous She is dancing. Expresses that an action is currently happening and will continue into the future. Requires “am/is/are” plus a present participle.
Past Continuous I was writing a book. Expresses that a continuous action occurred in the past. Requires “was/were” plus a present participle.
Future Continuous She will be dancing. Expresses an ongoing action that will occur at a future time. Requires “will be” plus a present participle.
Present Perfect Continuous I have been writing this book for six months so far. Shows that something began in the past and continues into the present. Requires “has/have been” plus a present participle.
Past Perfect Continuous She had been dancing for hours before she collapsed. Shows that an ongoing action both began and ended in the past. Requires “had been” plus a present participle verb.
Future Perfect Continuous I will have been writing this book for eight months by the end of November. Used for actions that are expected to continue until a certain point in the future. Requires “will have been” plus a present participle.

If you are unsure about the verb tense in your writing:

  1. Think about when the action you’re describing happens or happened. You can use the table above to quickly see what each tense is typically used for.
  2. Make sure you use tenses consistently.
  3. Don’t be afraid to ask a native English speaking friend or proofreader to check that the verb tenses are clear throughout your writing.

This should help you avoid errors related to verb form in your work.

Adjective Order

Adjective order can be tricky for ESL writers, as even most native English speakers struggle to explain the “rules” here. Nevertheless, the conventional order of adjectives in English is:

  1. Quantity (e.g., “two eggs”)
  2. Value/opinion (e.g., “a good day”)
  3. Size (e.g., “a narrow gap”)
  4. Age (e.g., “an ancient secret”)
  5. Physical quality/shape (e.g., “a smooth surface”)
  6. Color/shade (e.g., “pink flamingos”)
  7. Origin/nationality (e.g., “the Canadian flag”)
  8. Material (e.g., “a glass eye”)
  9. Type/purpose (e.g., “a juggling ball”)

A good guideline is the more important a word is for describing something, the closer it should go to the noun. That is why we’d say “a red sports car” and not “a sports red car” (i.e., because the type of car is more important than its color for understanding what it is).

However, there are exceptions to this standard order. In “American black bear,” for instance, nationality comes before color because “black bear” is a compound noun (i.e., a noun made up of two words conventionally used together). As such, “black” actually specifies the type of bear, not just its color. And since type is more important than nationality, it goes nearer “bear.”

Another famous example is the Big Bad Wolf from Little Red Riding Hood. Going by the adjective order suggested above, “bad” (a value/opinion) should come before “big” (a physical quality). But if we say Bad Big Wolf, it sounds wrong. This is because we tend to put “i” before “a” when repeating a consonant sound (something called reduplication). So just as “zig zag” sounds more natural than “zag zig,” Big Bad Wolf sounds more natural than Bad Big Wolf. As such, if you’re unsure about adjective order, try saying the words out loud to see if they sound right. You could even ask a friend if you’re still not sure!

Apostrophe Usage

You can use apostrophes to indicate possession or missing letters in contractions. However, this punctuation mark is often misused, so let’s look at how apostrophes work in various situations and some common errors that you should try to avoid in your writing.

Possessive Apostrophe

Apostrophes are how we show that something belongs to someone or something else. Typically, we do this by adding an apostrophe and an “s” like this:

Nigel’s car needed extensive repairs.

The main exception to this rule is possessive pronouns (e.g., “its,” “his,” “her”), which do not require an apostrophe. So, for example, the pronoun “it” becomes “its” to show possession:

Nigel loved his car: its top speed was 210 km/h.

See the section on “its” and “it is” for more on this distinction. However, we can also look at some more cases where possessive apostrophes can be confusing.

Possessive Apostrophes After “S”

When a word already ends in the letter “s,” you can either:

  1. Add an apostrophe plus another “s” (e.g., Alanis’s grasp of irony…)
  2. Or just use the apostrophe by itself (e.g., Alanis grasp of irony…)

Both are acceptable in modern English as long as you’re consistent. However, if you have a style guide, you may want to check it for advice on which approach to use.

Plurals And Possessive Apostrophes

Possessive apostrophes always go after the final “s” in a plural. If we wanted to talk about two dogs with empty food bowls, for example, the apostrophe placement would be crucial:

The dogs’ bowls are empty.
The dog’s bowls are empty.

The first sentence above suggests multiple dogs and multiple bowls. But the second implies one dog with more than one bowl. And while this second sentence is not ungrammatical, it would still be an error if we were trying to discuss the bowls of more than one dog.

Separate Or Joint Ownership?

When two or more people own one thing, the correct place to use an apostrophe comes down to whether you’re talking about separate or joint ownership:

    1. When two or more people separately own the same type of thing, you should add an apostrophe after each person’s name.
    2. If two or more people jointly own something, you should treat them as a single “subject” and you only need one apostrophe.

For example, if two people both had a stamp collection, we might say:

Tims and Rachels stamp collections are very valuable.

Here, we use an apostrophe for both Tim and Rachel because we’re talking about two people with two separate stamp collections. This is also why we use the plural noun “collections” and plural verb “are.” But let’s imagine that Tim and Rachel share a stamp collection instead:

Tim and Rachels stamp collection is very valuable.

In this case, we only use one apostrophe because “Tim and Rachel” are a single unit known as a compound subject. This is also reflected in the singular noun “collection” and the singular verb “is,” so we can see the sentence is about a jointly owned collection.

This distinction can be harder to spot when dealing with a mass noun:

Bobs and Beryls luggage was lost in transit.
Bob and Beryls luggage was lost in transit.

In the first sentence, Bob and Beryl have each lost their own luggage. In the second, Bob and Beryl have lost their shared luggage. And since “luggage” is always singular, we need the apostrophes to tell us who owns what. In cases like this, apostrophe use is crucial!

Indicating Contractions

We use an apostrophe in contractions to indicate missing letters:

Do not
I have
You are
It is

Another common contraction is to add an “-’s” to a word when it’s followed by “is” or “has”:

David is running late
David’s running late
His car has broken down
His car’s broken down

The main thing to note here is that you should not typically use contractions in formal writing (e.g., an essay). In such cases, it is much better to write out the full terms.

Never Use Apostrophes For Plural Nouns

One common error is to put an apostrophe before an “s” when forming a plural. But this is NEVER CORRECT! The plural of “dinosaur,” for example, is “dinosaurs,” not “dinosaur’s.”

So apostrophes can be used to show:

  • Who owns something (i.e., possession)
  • Missing letters in a contraction

But they are not needed and should not be used if you’re simply forming a plural.

Capitalization Errors

Different languages have different rules about capitalization. This makes it easy to miss capital letters or add them where they’re not necessary. As a guideline, though, the letters and words you’ll need to capitalize in English include:

  • The first letter of the first word in a sentence
  • The personal pronoun “I”
  • Titles of books and other media
  • Honorifics (e.g., Mr., Mrs., Dr., Prof.)
  • Acronyms and initialisms (e.g., NASA, CIA, FBI)
  • Proper nouns

We’ll look at a couple of these in more detail below, plus some things not to capitalize.

Proper Nouns

A proper noun is a noun that identifies a unique individual, such as a specific person, city, or landmark. For instance, the word “building” is a “common” or generic noun. But “Empire State Building” is a proper noun as it refers to a specific building in New York.

Other types of proper nouns to look out for in your writing include:

  • Personal names (e.g., Abraham Lincoln)
  • Brand names and companies (e.g., Microsoft, Coca-Cola)
  • Names of religions and deities (e.g., God, Islam, Buddha)
  • Geographical features and locations (e.g., the Grand Canyon, Quebec)
  • Languages and words related to nationality (e.g., Englishman, Spanish, Canadian)
  • Months and days of the week (e.g., Tuesday, October)
  • Special dates and events (e.g., New Year’s Day, the Olympic Games)
  • Important historical events (e.g., World War One)
  • Job titles used before a name (e.g., Chief Executive Bob Smith)
  • Planets (e.g., Mars, Jupiter, Earth)

All these terms should be capitalized unless there is a reason to use lowercase instead.

What NOT To Capitalize

Some common nouns are often capitalized by mistake. These include:

  • Seasons (e.g., spring, summer, fall, winter)
  • Academic subjects used in isolation (e.g., physics, media studies)
  • The word “god” when used generically (e.g., “gods and goddesses”)
  • Job titles when not used with a name (e.g., “I am a chief executive”)
  • The word “earth” when used for dirt rather than the planet
  • “Sun” and “moon” except when referring to the Earth’s Sun and Moon

These rules can vary, though, so make sure to check your style guide if you have one.

Title Case And Sentence Case

Finally, you may need to capitalize the titles of media products or documents. However, this depends on whether you’re using title case or sentence case:

  • In title case, you would usually capitalize the first word of the title and subtitle plus all major words (i.e., nouns, verbs, adjectives, and adverbs).
  • In sentence case, you would only capitalize the first word of the title and subtitle.

Make sure to check your style guide if you’re not sure which approach to use. And make sure to apply one style consistently (including in your own titles and for titles of published works).

Run-On Sentences

Run-on sentences occur when two sentences get jammed together without either correct punctuation or a conjunction. This may be because someone has missed a period:

Writing is fun I am going to write a book.

Or it can occur when someone uses a comma in place of a period (i.e., a “comma splice”):

Writing is fun, I am going to write a book.

If you see a run-on sentence in your writing, you can fix it in various ways:

  1. Placing a period between each clause.
  2. Adding a coordinating conjunction after the comma.
  3. Replacing the comma with a semicolon.
  4. Changing the first clause into a subordinate clause.

We will look at each of these in a little more detail below.

Placing A Period Between Each Clause

We can fix run-on sentences by using a period to separate the clauses:

Writing is fun. I am going to write a book.

This is often the simplest way to fix comma splices. However, if you want to emphasize or clarify the connection between two sentences, you have some alternatives available.

Adding A Coordinating Conjunction

Conjunctions are connecting words, so we can add one to fix a run-on sentence:

Writing is fun, so I am going to write a book.

Note that we still have a comma here between the clauses before the conjunction. This isn’t strictly necessary if connecting short sentences, but it is good practice for clear writing.

Adding A Semicolon

We can use a semicolon between two clauses to show they are related:

Writing is fun; I am going to write a book.

Remember, though, that semicolons can only be used to connect full sentences.

Using A Subordinate Clause

While commas can’t be used to connect two main clauses, they can be used when a subordinate clause comes before the main clause in a sentence. Thus, if we change the first clause in a run-on sentence to a subordinate clause, we can fix the error:

Because writing is fun, I am going to write a book.

As shown above, a subordinate clause includes a subordinating conjunction – in this case, “because” – and does not form a full sentence by itself. But by changing the first clause into a subordinate clause, we now have a grammatical sentence.

We could also rearrange the sentence so the main clause comes first:

I am going to write a book because writing is fun.

In this case, we do not need a comma to separate the two clauses.

Comparatives And Superlatives

We use comparatives and superlatives to compare things (e.g., to say something is “better” than something else or to pick out the “best” thing from a group).

We use comparative adverbs and adjectives to compare two things:

Your house is bigger than my house.

The comparative “bigger” here shows that we’re comparing the size of two houses.

We use superlatives, meanwhile, to show that something has the most or highest degree of some quality. However, this only applies when discussing a group of at least three things:

She has the biggest house in the neighborhood.

Here, for instance, we’re discussing the entire neighborhood, and we use the superlative “biggest” because there may be many houses in a neighborhood.

However, it isn’t always obvious how to form the comparative or superlative form of a word. As such, we’ll look at some helpful guidelines for using these terms below.

Forming Comparatives And Superlatives

Many comparatives end with “-er” and many superlatives end with “-est.” These spellings are used when forming a comparative or superlative from either of the following:

  1. All single-syllable words (e.g., small smallersmallest)
  2. Most two-syllable terms (e.g., happyhappierhappiest)

In other cases, we form comparatives and superlatives by adding the words “more” or “most” before an adjective or adverb. This is applies when the base term is:

  1. Two syllables and ends “-ful,” “-ous,” or “-less” (e.g., famousmore famousmost famous)
  2. An adverb ending in “-ly” (e.g., slowlymore slowlymost slowly)
  3. Three syllables or more (e.g., interesting → more interesting → most interesting)

Some two-syllable words can use either approach (e.g., you can say either “more narrow” or “narrower”). However, “-er” and “-est” endings are more concise and often preferable.

Irregular Comparatives And Superlatives

We also have some irregular comparative and superlative terms, including common words such as “better” and “best.” These particular terms are the comparative and superlative forms of “good” and “well” (hence we don’t say “gooder” or “goodest”).

Key irregular comparatives and superlatives to remember include:

Base Adjective/Adverb Comparative Superlative
Good/Well Better Best
Bad/Badly Worse Worst
Much/Many/Some More Most
Little Less Least
Far Further/Farther Furthest/Farthest

As you can see, these terms don’t follow a specific pattern. The best way to avoid errors is thus to memorize the comparative and superlative forms of irregular adjectives and adverbs.

Not Proofreading!

Okay, “not proofreading” is not uniquely an ESL error. Native English speakers also overlook proofreading, letting errors slip into their writing. But when you’re writing in a non-native language, having an expert available to check for errors is even more valuable.

You can, of course, ask a native English speaking friend or colleague to check your work. But to be sure your writing is error free, you can also use a professional proofreading service.

For instance, with Proofed, you can be confident your work is in the hands of an expert, and we will provide helpful feedback on your writing, with links to in-depth articles explaining the corrections we make. Thus, as well as proofreading your work, we also help you grow as a writer. Why not upload a document today and see what we can do for you?

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