Common Grammar Mistakes and How to Fix Them

The Most Common Grammar Mistakes

Everyone makes grammar mistakes — even professional writers. The key is knowing what to look for and having tools to catch what you miss. Here are the most common grammar mistakes and how to fix them.

1. Subject-Verb Agreement

The subject and verb must agree in number. This is one of the most frequent errors.

Wrong: "The list of items are on the desk."

Right: "The list of items is on the desk."

The subject is "list" (singular), not "items," so the verb should be "is."

2. Their / There / They're

These homophones cause endless confusion:

• Their = possessive ("their house")
• There = location ("over there")
• They're = they are ("they're coming")

3. Its vs. It's

• Its = possessive ("the dog wagged its tail")
• It's = it is ("it's raining")

This trips up even experienced writers because we normally use apostrophes for possession.

4. Comma Splices

A comma splice joins two independent clauses with just a comma.

Wrong: "I went to the store, I bought milk."

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

5. Misplaced Modifiers

Wrong: "Walking to school, the rain started falling."

Right: "Walking to school, I noticed the rain starting to fall."

The modifier should be next to the word it describes.

6. Tense Inconsistency

Switching tenses within a paragraph is a common mistake. Pick a tense and stick with it unless there's a reason to change.

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