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3 Grammar Mistakes That Cost You Marks

📅 March 1, 2026 ✍️ IELTS Corner Team ⏱️ 5 min read

IELTS students lose marks for the same grammar mistakes over and over. In this article, we show you the 3 most common errors—and how to fix them.

Mistake #1: Subject-Verb Agreement

❌ Incorrect:"The number of students who studies English are increasing."

✓ Correct: "The number of students who study English is increasing."

Why it happens: We look at the nearest noun ("students"), but the subject is actually "the number" (singular).

Rule: The subject is usually the noun closest to the verb, right? No! The subject is the main noun phrase, not the one in the middle.

Examples:

  • "The group of people is large." (group = subject)
  • "The series of events has changed." (series = subject)
  • "The majority of students get Band 6." (majority = subject)

Practice: Identify the main noun (subject). Ignore words in the middle. Match the verb to that noun only.

Mistake #2: Adding Extra Subjects

❌ Incorrect: "My sister, she lives in Canada."

✓ Correct: "My sister lives in Canada."

Or with a relative clause:

❌ Incorrect: "The students who want to study, they need to prepare."

✓ Correct: "The students who want to study need to prepare."

Why it happens: In some languages, repeating the subject is normal. In English, it's redundant and incorrect.

Rule: Don't repeat the subject. One subject per verb.

Mistake #3: Wrong Word Order (Inversion)

❌ Incorrect: "I have never seen such difficulty a test."

✓ Correct: "I have never seen such a difficult test."

Another example:

❌ Incorrect: "Under no circumstances I will accept this."

✓ Correct: "Under no circumstances will I accept this." (or avoid inversion: "I will not accept this.")

Why it happens: You're trying to sound formal but getting the word order wrong. Inversion is tricky!

Safe rule: Unless you're sure about inversion, keep the normal word order: Subject + Verb + Object.

How to Avoid These Mistakes

  1. Read your writing aloud. Your ear will catch many grammar mistakes.
  2. Find the main subject first. Ignore prepositional phrases and relative clauses.
  3. Don't repeat the subject. "She lives in Canada" (not "She, she lives...").
  4. Keep word order simple. Subject + Verb + Object is safest.
  5. Practice with our lessons. We have 81 grammar lessons covering all these structures.

Next Steps

Want to master these structures? Check out our lessons on:

Or get personalized help from a tutor.

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