Learning English as a second language is an exciting journey, but grammar can sometimes feel confusing and overwhelming. Even advanced ESL students make small mistakes that affect clarity and confidence when speaking or writing. The good news is that most grammar errors are predictable and easy to fix once you understand the patterns behind them.

In this article, we’ll explore some of the most common grammar mistakes ESL students make and provide simple strategies to correct them.

1. Confusing Verb Tenses

One of the most frequent challenges for ESL learners is choosing the correct verb tense. English has many tenses, and they don’t always exist in other languages in the same way.

Common mistake:
“I went to the store yesterday.”

Correct form:
“I went to the store yesterday.”

This error happens because students often translate directly from their native language. In English, past events require a past tense verb.

How to fix it:

• Learn time markers like yesterday, last week, and ago—they usually signal past tense.

• Practice using verb charts and writing short daily journals to reinforce correct tense usage.

2. Subject–Verb Agreement Errors

In English, verbs must agree with the subject in number (singular or plural). This seems simple, but it causes many mistakes, especially in the present tense.

Common mistake:
“She goes to school every day.”

Correct form:
“She goes to school every day.”

The “-s” ending in the third-person singular is easy to forget but very important for grammatical accuracy.

How to fix it:

• Remember the rule: He, she, and it → add -s or -es to the verb.

• Practice with repetition and speaking exercises until it becomes automatic.

3. Misusing Articles (a, an, the)

Articles are one of the hardest parts of English grammar because many languages do not use them in the same way—or at all.

Common mistakes:

• “I bought a car yesterday.”

• “She is the doctor” (when introducing her for the first time)

Correct forms:

• “I bought a car yesterday.”

• “She is a doctor.”

How to fix it:

• Use a/an for something general or mentioned for the first time.

• Use it when both the speaker and listener know what is being discussed.

Reading regularly in English is one of the best ways to develop a natural understanding of article usage.

4. Incorrect Prepositions

Prepositions like in, on, at, to, and for are small words, but they often cause big problems for ESL learners.

Common mistakes:

• “I am married to him.”

• “She arrived at the airport.”

Correct forms:

• “I am married to him.”

• “She arrived at the airport.”

Prepositions rarely follow logical rules, so they must often be memorized as part of phrases.

How to fix it:

• Learn prepositions together with verbs and expressions, not individually (for example: arrive at, depend on, interested in).

• Keep a personal list of common verb–preposition combinations.

5. Problems with Plurals

Many ESL students forget to make nouns plural or use irregular plural forms incorrectly.

Common mistakes:

• “I have two brothers.”

• “There are many children in the park.”

Correct forms:

• “I have two brothers.”

• “There are many children in the park.”

How to fix it:

• Always check whether the number is plural and add -s or -es when needed.

• Memorize common irregular plurals like children, people, men, and women.

6. Word Order in Sentences

English has a strict sentence structure: Subject + Verb + Object. Learners who speak languages with more flexible word order often struggle with this.

Common mistake:
“I very much like this movie.”

Correct form:
“I like this movie very much.”

How to fix it:

• Practice building sentences using the standard structure.

• Reading and listening to natural English conversations can help you internalize correct word order.

7. Using Double Negatives

In some languages, double negatives are normal. In English, however, they create incorrect or confusing sentences.

Common mistake:
“I don’t know nothing.”

Correct form:
“I don’t know anything.”

How to fix it:

• Remember: In standard English, only one negative word should be used in a sentence.

Making grammar mistakes is a natural part of learning any language. Even native speakers sometimes make errors in casual conversation. What matters most is recognizing your mistakes, understanding why they happen, and practicing the correct forms consistently.

The key to improvement is regular exposure to English through reading, writing, listening, and speaking. With time and practice, these common grammar mistakes become easier to avoid, and your confidence in using English will grow.

At ASC English, we help students identify their personal grammar challenges and provide targeted practice to help them communicate clearly and naturally. If you’d like to strengthen your grammar and fluency, our programs are designed to support you at every stage of your learning journey.