Grammar & vocabulary

15 Common IELTS Mistakes (and How to Fix Them)

The grammar, vocabulary and exam-technique mistakes that most often cost IELTS candidates half a band, with quick fixes.

All levels 8 min readUpdated 31 October 2026

Examiners see the same errors thousands of times. Fixing the ones below is often the quickest way to gain half a band.

Grammar

  1. Uncountable nouns with "s": informations, advices, researches, equipments → information, advice, research, equipment.
  2. Missing articles: Government should invest in education → The government should invest… (but education in general takes no article).
  3. Subject–verb agreement: The number of students have risen → The number of students has risen. (But: A number of students have…)
  4. "People" is plural: People is… → People are….
  5. Comma splices: Prices are rising, people are worried → Prices are rising, so people are worried or two sentences.

Vocabulary

  1. Confused pairs: affect (verb) vs effect (noun); rise (no object) vs raise (with object); lose vs loose.
  2. Wrong collocations: make a crime → commit a crime; do a mistake → make a mistake; strong rain → heavy rain.
  3. Informal words in essays: kids, a lot of, stuff, nowadays everybody → children, a significant number of, things, many people today.
  4. Overusing "big" and "good": try substantial, considerable, significant, beneficial, effective.
  5. Memorised idioms in essays: "It's raining cats and dogs" or "a piece of cake" sound unnatural in academic writing. Use idioms sparingly in Speaking only.

Exam technique

  1. Ignoring word limits in Listening and Reading. NO MORE THAN TWO WORDS means exactly that.
  2. No overview in Task 1. Without one, Task Achievement is limited.
  3. Changing your opinion in Task 2: decide your position before writing.
  4. Short Speaking answers in Parts 1 and 3. Extend with reasons and examples.
  5. Leaving blanks. There is no penalty for a wrong answer, so always guess.

Spot the mistakes: a practice paragraph

This short paragraph contains six of the mistakes above. Try to find them before reading the answers.

Nowadays, kids spends a lot of time on their phones. This have a bad affect on their health, and parents should give them more advices about it. Despite of the risks, many schools allow phones in class.

Corrections:

  1. kids → children (informal word in an essay)
  2. spends → spend (subject–verb agreement with a plural subject)
  3. This have → This has (singular subject)
  4. a bad affect → a negative effect (affect/effect confusion, and bad is vague)
  5. more advices → more advice (uncountable noun)
  6. Despite of the risks → Despite the risks (no of after despite)

Improved version:

Children today spend a considerable amount of time on their phones. This can have a negative effect on their health, and parents should give them clear advice about it. Despite the risks, many schools still allow phones in class.

The improved version is not more complicated. It is simply more accurate and more precise, which is exactly what moves a score from band 6 to band 7.

Mistakes in Speaking

  • Answering too briefly in Parts 1 and 3. Extend every answer with a reason and an example.
  • Correcting every small slip. One quick self-correction is fine; stopping repeatedly hurts fluency.
  • Speaking too fast to sound fluent. Clear, steady speech with natural pauses scores better on pronunciation.

How to stop repeating your mistakes

Keep an error log, a simple table with three columns:

My mistake Correct form Rule
an advice a piece of advice advice is uncountable
despite of the cost despite the cost despite + noun, no "of"

Review it for five minutes before every practice session. Most candidates have only five to ten personal repeated errors, and eliminating them makes a visible difference.

Test yourself with the vocabulary flashcards and check your essays with the AI feedback tool.