After coaching hundreds of English learners, I have noticed a pattern. Most people make the same grammar mistakes, over and over. The good news is that these mistakes are easy to fix once you know what to look for.
Here are the 10 most common grammar mistakes I see, with simple explanations and examples.
1. Subject-Verb Agreement with Third Person Singular
The mistake: "He go to work every day."
Should be: "He goes to work every day."
This is the most common mistake in English. With he, she, and it, you need to add -s to the verb in present tense. I go, you go, we go, they go, but he goes, she goes, it goes.
Tip: Every time you say "he" or "she," check if your verb has an -s. Train yourself to hear the difference.
2. Using the Wrong Past Tense
The mistake: "Yesterday I go to the store."
Should be: "Yesterday I went to the store."
Irregular verbs are the hardest part of English grammar. Go becomes went, not goed. Buy becomes bought, not buyed. There is no rule. You just have to memorize them.
Tip: Make a list of the 20 most common irregular verbs and practice them until they feel natural. Say them out loud.
3. Missing Articles (a, an, the)
The mistake: "She is teacher."
Should be: "She is a teacher."
Languages like Japanese, Korean, Chinese, Russian, and many others do not use articles. So it is natural to forget them. But English uses articles constantly.
Tip: After you say a sentence, check if you missed any a, an, or the. With practice, it becomes automatic.
4. Prepositions at the Wrong Place
The mistake: "I am married with a doctor."
Should be: "I am married to a doctor."
Prepositions are tricky because they do not translate directly between languages. Other common ones: interested in (not on), depend on (not of), good at (not in).
Tip: When you learn a new verb, learn the preposition that goes with it. Treat them as a pair.
5. Confusing Since and For
The mistake: "I have lived here since three years."
Should be: "I have lived here for three years."
Use for with a duration (for three years, for a week, for a long time). Use since with a starting point (since 2020, since Monday, since I was a child).
6. Word Order in Questions
The mistake: "You are from where?"
Should be: "Where are you from?"
In English, question words go at the beginning. The subject and verb also switch places. Statement: "You are a student." Question: "Are you a student?"
7. Using the Wrong Conditional Form
The mistake: "If I will have time, I will come."
Should be: "If I have time, I will come."
In first conditional sentences (real possibility), use present tense in the if-clause and will in the result clause. Do not use will in both parts.
8. Countable and Uncountable Nouns
The mistake: "I need some advices."
Should be: "I need some advice."
Advice, information, knowledge, news, furniture, and many other nouns are uncountable in English. You cannot add -s to them.
9. Using the Wrong Verb After a Modal
The mistake: "I can to swim."
Should be: "I can swim."
After modal verbs (can, should, must, might, will), use the base form of the verb without to. I can go. You should try. She must leave.
10. Confusing Much and Many
The mistake: "I have much friends."
Should be: "I have many friends."
Use many with countable nouns (many friends, many books, many cars). Use much with uncountable nouns (much water, much time, much money).
How to Stop Making These Mistakes
Reading about these mistakes is the first step. But knowing and doing are different things. The real improvement happens when you catch yourself making the mistake in real time and correct it.
This is where practicing with an AI coach helps. Every time you speak, the coach catches these mistakes and shows you the correction. Over time, your brain learns the correct pattern and the old mistakes fade away.
Frequently Asked Questions
Which grammar mistake is the most common?
Subject-verb agreement with third person singular is the most common mistake. Learners often say he go instead of he goes. Focus on this one pattern for a week and you will see a big improvement.
How can I fix my grammar mistakes faster?
Get real-time corrections while you speak. When an AI coach corrects you the moment you make a mistake, your brain learns the correct pattern faster than studying rules on your own.
Is it okay to make grammar mistakes when speaking?
Yes. Making mistakes is part of learning. The goal is not to be perfect. The goal is to communicate and improve over time.