The No-Shame Guide to Common Grammar Mistakes in English

If you search online for guides on English grammar, chances are that you’ll find articles written by editors talking about their pet peeves and about how terrible it is to see such-and-such grammar mistake.

That’s not how we see it.

Here’s the truth: Everyone makes English grammar mistakes. English learners, native-speaking children, and educated adults — they all make grammar mistakes every day. And that’s okay, especially when speaking. However, when it’s time to give a presentation at work or write a cover letter for a new job, it helps brush up on your grammar. Above all, proper grammar in a formal setting shows that you pay attention to detail and understand how to act in a professional environment.

In other settings, proper English grammar helps in social situations. We’re here to help prepare you for those situations.

Whether you’re new to the English language or a native speaker looking for a quick refresher course, this guide will help you polish your English grammar skills.

A quick review of English grammar terms

• Contractions are two words that you can put together to form a single word. For example, instead of “I am,” many people say “I’m.” Contractions are common in spoken English, but you should always write out the full words in formal writing.
• Independent clauses can stand alone as a complete thought. “I’m staying home,” is an example of an independent clause because it’s a complete thought or complete sentence.
• Dependent clauses cannot stand alone as a complete thought. Consider the sentence, “If it rains, I’m staying home.” Here, the phrase “If it rains” is an example of a dependent clause because we need more information before we can consider it a complete thought.
• Pronouns are words that can replace other nouns. Words like “I,” “he,” and “they” are examples of pronouns.
• Possessive pronouns are pronouns that have to do with something belonging to someone or something. “My,” “his,” and “our” are examples of possessive pronouns.

A quick guide to English punctuation

If you’re new to English, you may see or read about different punctuation marks. Here are the names of the most common punctuation marks in English.

.	period
,	comma
!	exclamation point
?	question mark
:	colon
;	semicolon
‘	apostrophe
“”	quotation marks or quotes
/	slash
( )	parentheses

1. Similar words that are used differently

In some cases, there are words that have very similar meanings but are used in different situations. Here are some examples of commonly confused words:

Less and fewer

“Less” is used for uncountable things such as water, air, or time in the general sense.

A cactus needs less water than other plants.

I have less time for video games now that I’m an adult.

You should also use “less” for units such as fractions and units of time.

Less than half of the team came to the meeting.

I did my homework in less than an hour.

“Fewer” is used for countable or numbered things.

You’re making fewer grammatical errors than before.

There are fewer than 100 people in my office.

Lay and lie

“Lay” needs an object. In other words, you need something to lay or lay down.

Please lay the book on the table when you’re done.

The soldiers lay down their weapons.

“Lie,” on the other hand, doesn’t have an object. 

You look tired. Go lie down and take a nap.

Lying on the floor of the messy room were dirty clothes.

Who and that

In general, use “who” to refer to people and “that” to refer to things.

She’s a woman who knows what she wants.

I live in a building that doesn’t have an elevator.

I and me

Most people have no trouble using “I” and “me” correctly when there’s only one person in a sentence:

I like ice cream.

She needs to talk to me.

It can get confusing when there are multiple people in a sentence. A good rule is to take away the other people in the sentence. Then ask yourself: which word fits better, “I” or “me”?

Carlos and I like ice cream.

Carlos and I like ice cream.

She needs to talk to Mary and me.

She needs to talk to Mary and me.

2. Words that sound the same but are written differently

English is well known for its unusual spelling rules. It doesn’t help that English also has many homophones, which are words that sound the same but are spelled differently. Here are some common examples:

To, two, and too

“To” commonly indicates direction.

They walked to the park.

The word “to” is also used to connect verbs with words such as “have” and “going.”

I have to wake up early.

He’s going to make us dinner.

“Two” refers to the number.

I have two daughters.

“Too” is a word that means “also.”

I have a son, too.

There, they’re, and there

“There” refers to a place.

Let’s go to the park. I haven’t been there in weeks!

“They’re” is a contraction of two words, “they” and “are.”

They’re going to the park tomorrow. (They are going to the park tomorrow.)

“Their” is a possessive pronoun that means “belonging to them.”

My parents sold their house last year.

You’re and your

 “You’re” is a contraction of two words, “you” and “are.”

You’re so intelligent! (You are so intelligent!)

“Your” is a possessive pronoun that means “belonging to you.”

May I borrow your pen?

Than and then

“Than” is used in comparisons.

Earth is smaller than the sun.

There are more than 6,000 languages in the world.

“Then” is used to describe actions in time.

We went to the park, and then we got ice cream.

Back then, people used phone lines to connect to the Internet.

It’s and its

“It’s” is a contraction of two words, “it” and “is.”

It’s a beautiful day today. (It is a beautiful day today).

“Its” is a possessive pronoun that means “belonging to it.”

The cat licked its paws.

Who’s and whose

“Who’s” is a contraction of the two words “who” and “is.”

Who’s going to the party tonight? (Who is going to the party tonight?)

“Whose” is a possessive pronoun most commonly used in questions.

Whose coat is this?

In more formal writing, “whose” is also used as a relative pronoun.

We threw a party for my mother, whose birthday is today. 

3. Possessive markers for plurals

You might already be familiar with the possessive marker for singular nouns in English. We simply add an apostrophe and the letter “s.”

This is Sarah’s house.

But what about for plurals? For plurals that already end in “s,” all you need to do is add an apostrophe to make the word possessive.

This is the boys’ room.

Just remember that plurals that don’t end in “s” get the standard treatment.

We went to the children’s school.

4. When to use a comma

Whether you’re a native English speaker or learning the language for the first time, comma use in English can be very confusing. Here are seven basic rules on when to use a comma:

1. To separate two independent clauses with FANBOYS

When deciding when to use a comma in English, you should first remember your FANBOYS:

• For
• And
• Nor
• But
• Or
• Yet
• So

These seven words are officially known as coordinating conjunctions, but we’ll just call them FANBOYS. FANBOYS are words that connect clauses in English.

If your sentence has two independent clauses connected by FANBOYS, then you should use a comma. Remember that independent clauses can stand alone as complete thoughts.

I went to the beach, but I didn’t go in the water.

Since both parts of this sentence can stand alone as independent clauses, you should use a comma.

2. To separate items in a list

If you have more than two items in a list or series, then you should separate them with a comma.

Would you like coffee, tea, or juice?

We’ll drive to Miami, go to the beach, and eat Cuban food this weekend.

3. To address someone

If you’re using someone’s name to get their attention, you should use a comma to separate the name. 

Jake, I believe you’re right.

I believe you’re right, Jake.

I believe, Jake, that you’re right.

4. To separate an introductory phrase

When you start a sentence with an introductory word or phrase, the comma lets the reader know that the main part of the sentence is about to begin.

Whenever I pet my cat, I feel more relaxed.

With over 1.3 billion total speakers, English is the most widely spoken language in the world.

Tomorrow, she’s going to the movies.

5. To separate nonessential information

If there is information that’s not essential to the meaning of a sentence, use a comma.

My sister, who often stays up late, is sleeping.

In China, a country in Asia, there are many large cities.

6. To separate direct quotations

If you are using quotations to write dialogue or conversation, use commas to separate the quote from the rest of the sentence.

Michael asked, “How many hours are in a year?”

“I don’t know,” replied Becky.

“In that case,” said Michael, “I’ll check online.”

7. To separate dates, places, and numbers

Cities, regions, and countries should be separated from each other with commas.

I was born in Uttar Pradesh, India, but I now live in Atlanta, Georgia.

Days and years are separated from each other with commas.

On June 2, 1953, Queen Elizabeth II was crowned in Westminster Abbey.

Also, separate numbers larger than 999 with commas.

There are 8,760 hours in one year.

5. Which dash to use

Believe it or not, English uses three kinds of dashes. Each dash has its own function, and lots of people mix them up. Here’s when you should use each type of dash:

The hyphen

Use a hyphen to join words together in compound adjectives that come before the noun.

Michael Jackson was a well-known pop artist.

Is this a dog-friendly hotel?

Note that words that end in “-ly” don’t need a hyphen.

Buddhism is a widely practiced religion.

Also, note that the hyphen isn’t used for compound adjectives that come after the noun.

Michael Jackson was a pop artist who was well known.

The en dash

The en dash is most commonly used to separate ranges of times or numbers.

Please do pages 40–45 for homework.

My meeting is from 8:00–9:00.

The em dash

Use the em dash in a sentence to highlight special information in a sentence.

My neighbor — who has never spoken to me since he moved in 10 years ago — invited me to his birthday party.

6. When to use simple present and present progressive

If you’re a non-native English speaker, some verb tenses are especially tricky. One of the most common grammar mistakes is incorrectly using the simple present tense (“I do”) or the present progressive tense (“I am doing”).

First, don’t stress about this. You’re not alone in making this grammatical mistake. Second, there are a few guidelines to help you understand which tense to use.

Present progressive

Use the present progressive to describe things that are happening at the moment.

What are you doing?

I’m reading an article about English grammar.

The present progressive also describes events that have been planned or arranged.

Tomorrow, I’m visiting my mother.

Simple present

Use the simple present to describe things that happen regularly. Keywords include “often” and “always,” but also “never.”

I often get an order of fries when I order a burger.

She always brushes her teeth before bed.

I never eat dessert before dinner.

Simple present is also used to describe actions that happen on a schedule.

The bus leaves at 6:00 p.m.

Finally, verbs like “have,” “want,” “understand,” “know,” and “live” are almost always used in the simple present.

I have two cats.

My son wants a cell phone for his birthday.

I understand what you mean.