10 Common English Grammar Mistakes (and How to Fix Them)

Published: May 18, 2026 · 8 min read

Even native speakers make these mistakes. Here are the 10 most common English grammar errors, with clear examples of what's wrong and how to fix each one.

1. Subject-Verb Agreement

The subject and verb in a sentence must agree in number. A singular subject takes a singular verb; a plural subject takes a plural verb.

Wrong: The list of items are on the desk.
Right: The list of items is on the desk.

The true subject is "list" (singular), not "items." Prepositional phrases between subject and verb don't change the agreement rule.

2. Your vs You're

Your is possessive — it means something belongs to you. You're is a contraction of "you are."

Wrong: Your going to love this.
Right: You're going to love this.

Quick test: replace it with "you are" in your head. If it makes sense, use "you're."

3. Their vs There vs They're

Their = possessive (belongs to them). There = location. They're = contraction of "they are."

Wrong: Their going to the store over there.
Right: They're going to the store over there.

4. Its vs It's

Its is possessive. It's is a contraction of "it is" or "it has." This one tricks people because apostrophe-s usually shows possession — but not with "it."

Wrong: The cat licked it's paw.
Right: The cat licked its paw.
Right: It's raining outside.

5. Comma Splices

A comma splice happens when two independent clauses are joined with only a comma.

Wrong: I went to the store, I bought milk.
Right: I went to the store, and I bought milk.
Right: I went to the store. I bought milk.

6. Dangling Modifiers

A modifier at the beginning of a sentence must describe the subject. When it doesn't, you get a dangling modifier.

Wrong: Walking down the street, the flowers were beautiful.
Right: Walking down the street, I saw beautiful flowers.

7. Me vs I

Use I when you're the subject, me when you're the object. The trick: remove the other person from the sentence.

Wrong: The teacher gave the book to John and I.
Right: The teacher gave the book to John and me. (gave to me — not "gave to I")

8. Fewer vs Less

Use fewer for countable nouns, less for uncountable nouns.

Wrong: There are less cars on the road today.
Right: There are fewer cars on the road today.
Right: There is less traffic today.

9. Then vs Than

Then = time/sequence. Than = comparison.

Wrong: I'm taller then my brother.
Right: I'm taller than my brother.
Right: I ate lunch, then I went for a walk.

10. Who vs Whom

Who = subject (does the action). Whom = object (receives the action).

Wrong: Who did you give the book to?
Right: Whom did you give the book to? (you gave it to him — use "whom")

He → who, Him → whom. If you can answer the question with "him," use "whom."

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