IELTS grammar mistakes to avoid for Band 8 writing
The grammar mistakes that keep IELTS Writing at Band 6.5—articles, subject-verb agreement, sentence fragments and comma splices—and how to fix each one.
By English Grader study guides · AI-assisted educational content · Official sources linked below
The short answer
Band 8 grammar means 'the majority of sentences are error-free'—you do not need perfect English, you need to eliminate your three most frequent errors.
Articles: a, an, the
Article errors are the most common mistake at Band 6.5. The rule that fixes most cases: use 'the' when the reader knows which one you mean; use 'a/an' for first mention of something countable.
'The government should invest in the public transport' is wrong—'public transport' is uncountable and general, so no article.
- First mention: 'a university'
- Known to reader: 'the university I attended'
- General plural/uncountable: no article
Subject-verb agreement
Long subjects hide the real noun: 'The number of students who study abroad have increased' is wrong—'the number... has increased'.
Watch for 'one of the + plural noun + singular verb': 'One of the biggest problems is...'
Related guide: More grammar mistakes
Fragments and comma splices
A fragment is an incomplete sentence: 'Because the cost of living is rising.' cannot stand alone.
A comma splice joins two sentences with only a comma: 'The population is growing, this causes problems.' Use a full stop, a conjunction, or a semicolon.
- Fragment fix: attach it to the main clause
- Splice fix: full stop, 'which', or 'and/but/so'
Practise
Submit an essay and count how many of these three errors appear—then rewrite those sentences.
Start Writing Task 2 →Put this into practice
Submit an essay and see exactly which grammar errors are limiting your band.
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Official sources and further reading
Practice examples and study routines are illustrative advice, not official band-scored answers or predictions of exam questions.