Grammar
50 Common Grammar Mistakes in English (With Examples and Corrections)
By Professor Rachel Thompson, MA TESOL & ESL Curriculum Developer on March 26, 2026
Professor Rachel Thompson, MA TESOL
ESL Curriculum Developer & Grammar Specialist with 20+ years teaching English to non-native speakers. Former Cambridge English Assessment consultant and author of 3 grammar textbooks used in 40+ countries. Specialist in error analysis and learner corpus research.
Quick Summary
Grammar mistakes affect 94% of English learners, but research from the Cambridge English Corpus shows that 78% of errors fall into just 5 categories: articles, verb tense, subject-verb agreement, prepositions, and homophones. This guide covers the 50 most common grammar mistakes with simple explanations and correct examples to help you improve your writing, boost your IELTS score (grammar = 25% of Writing score), and communicate more professionally.
?? Grammar Error Research: Key Statistics
Based on Cambridge English Corpus analysis of 20+ million learner texts:
94%
Learners make regular grammar errors
23%
Errors are article-related (a/an/the)
18%
Errors involve verb tense
25%
Of IELTS Writing score is grammar
Grammar mistakes are one of the biggest obstacles to clear and professional English communication. According to research from the Cambridge English Corpus, which analyzed over 20 million learner texts, 94% of English learners make grammar mistakes regularly. Whether you are preparing for IELTS, TOEFL, academic writing, or everyday communication, avoiding common grammar mistakes can significantly improve your writing quality and score.
In this guide, you will learn the 50 most common grammar mistakes in English, with simple explanations, wrong examples, and correct versions. The British Council recommends focusing on these high-frequency errors first, as eliminating them has the biggest impact on your writing clarity.
Why It Is Important to Avoid Grammar Mistakes
Grammar mistakes can:
- Reduce your IELTS Writing band score (grammar accounts for 25% of your Writing score)
- Make your writing look unprofessional
- Cause misunderstanding
- Affect academic and career success
The good news is that most grammar mistakes are easy to fix once you recognize them.
50 Common Grammar Mistakes (With Examples and Corrections)
1. Your vs You're
? Your very smart.
? You're very smart.
Explanation: You're = You are. Your = Possession.
2. Their vs There vs They're
? There house is big.
? Their house is big.
3. Its vs It's
? Its raining.
? It's raining.
4. Subject-Verb Agreement
? She go to school.
? She goes to school.
5. Using "a" and "an" Incorrectly
? She is a honest person.
? She is an honest person.
6. Missing Articles
? I bought car.
? I bought a car.
7. Incorrect Plural Form
? Childs are playing.
? Children are playing.
8. Using "Much" Instead of "Many"
? Much people came.
? Many people came.
9. Double Negatives
? I don't know nothing.
? I don't know anything.
10. Incorrect Preposition
? Married with her.
? Married to her.
11. Confusing Then and Than
? She is taller then him.
? She is taller than him.
12. Run-on Sentence
? I woke up I ate breakfast.
? I woke up, and I ate breakfast.
13. Fragment Sentence
? Because I was tired.
? I slept early because I was tired.
14. Incorrect Verb Tense
? Yesterday I go to school.
? Yesterday I went to school.
15. Missing Capital Letter
? i am happy.
? I am happy.
16. Apostrophe Error
? Dogs are cute's
? Dogs are cute
17. Confusing To, Too, and Two
? I am to tired.
? I am too tired.
18. Incorrect Comparative
? More better
? Better
19. Incorrect Superlative
? Most fastest
? Fastest
20. Using "Me" Instead of "I"
? Me and John went.
? John and I went.
21. Using "I" Instead of "Me"
? She gave it to John and I.
? She gave it to John and me.
22. Incorrect Word Order
? I only eat vegetables sometimes.
? I eat vegetables only sometimes.
23. Missing Comma
? Let's eat grandma.
? Let's eat, grandma.
24. Confusing Affect and Effect
? This will effect you.
? This will affect you.
25. Using "Less" Instead of "Fewer"
? Less people came.
? Fewer people came.
26. Incorrect Pronoun Reference
? John told Mike he is smart.
? John told Mike, "You are smart."
27. Confusing Who and Whom
? Who did you call?
? Whom did you call?
28. Incorrect Passive Voice
? The homework did by me.
? The homework was done by me.
29. Using "Very Unique"
? Very unique
? Unique
30. Incorrect Gerund Use
? I enjoy to swim.
? I enjoy swimming.
31. Confusing Lose and Loose
? I loose my keys.
? I lose my keys.
32. Confusing Accept and Except
? I except your offer.
? I accept your offer.
33. Incorrect Modal Verb
? He must to go.
? He must go.
34. Using "Since" Incorrectly
? I am here since Monday.
? I have been here since Monday.
35. Incorrect Conditional
? If I will see him, I will tell him.
? If I see him, I will tell him.
36. Confusing Borrow and Lend
? Borrow me money.
? Lend me money.
37. Incorrect Infinitive
? I made him to cry.
? I made him cry.
38. Confusing Say and Tell
? He said me the truth.
? He told me the truth.
39. Using "People is"
? People is happy.
? People are happy.
40. Incorrect Question Form
? You are coming?
? Are you coming?
41. Incorrect Past Participle
? I have went.
? I have gone.
42. Confusing Advice and Advise
? He adviced me.
? He advised me.
43. Incorrect Countable Use
? Informations
? Information
44. Using "He Don't"
? He don't like it.
? He doesn't like it.
45. Incorrect Reflexive Pronoun
? Myself went.
? I went.
46. Confusing Make and Do
? Do a mistake
? Make a mistake
47. Incorrect Time Expression
? Discuss about
? Discuss
48. Incorrect Word Form
? Beauty girl
? Beautiful girl
49. Using "More Easier"
? More easier
? Easier
50. Missing Verb
? She very smart.
? She is very smart.
Tips to Avoid Grammar Mistakes
- Read regularly
- Practice writing daily
- Learn grammar rules
- Review your mistakes
- Use grammar tools
Conclusion
Avoiding common grammar mistakes can dramatically improve your English writing. These 50 mistakes are the most frequent errors made by students and learners.
Mastering them will help you:
- Improve your IELTS score
- Write professionally
- Communicate clearly
Frequently Asked Questions
What are the most common grammar mistakes?
Common mistakes include Your vs You're, subject-verb agreement, incorrect verb tense, and missing articles.
How can I improve my grammar fast?
You can improve by practicing daily, reading English books, learning grammar rules, and reviewing your mistakes.
Is grammar important for IELTS?
Yes. Grammar directly affects your IELTS Writing band score.
Related Resources
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