There is a myth that a big vocabulary equals a high IELTS Writing band. It does not. The Lexical Resource descriptor at Band 7 rewards 'a sufficient range of vocabulary to allow some flexibility and precision' and 'some awareness of style and collocation'. The key words are precision and collocation, not rarity. A candidate who uses 'mitigate' correctly once scores higher than one who uses 'ameliorate' incorrectly three times.
The examiner is not counting rare words. They are noticing whether your word choices are accurate, natural, and varied enough to express your ideas without repetition.
1. Topic collocations: the vocabulary that carries
Collocations are words that naturally pair together in English: 'commit a crime', not 'do a crime'. 'Heavy traffic', not 'strong traffic'. The examiner hears these pairs thousands of times and notices immediately when they are wrong. Getting collocations right signals Band 7; getting them wrong signals Band 6.
Build collocations by topic, as our common topics guide recommends, not by memorising a list. When you read about an Education topic, note the phrases that keep appearing: 'formal curriculum', 'holistic development', 'critical thinking', 'standardised assessment'. Those are your collocations.
Band 6 (weak collocation)The government should do a strong plan to reduce the big problem of air pollution.
Band 7 (precise collocation)The government should implement a comprehensive policy to address the growing problem of air pollution.
Three collocation fixes: 'do a plan' → 'implement a policy', 'strong plan' → 'comprehensive policy', 'big problem' → 'growing problem'. The vocabulary is not rare, it is just precise in context.
2. Replace weak verbs
The verbs you use control the precision of your sentences. Weak verbs like 'do', 'make', 'get', 'have', and 'be' are grammatically correct but lexically empty. Replacing them with a more specific verb does more for your Lexical Resource score than adding a rare adjective ever could.
- Do a study → conduct a study
- Make a decision → reach a decision
- Get better → improve, recover
- Have an effect on → influence, shape
- Be important → matter, play a central role
- Make pollution worse → exacerbate pollution
- Get money from → generate revenue from
Do not replace every weak verb. One or two precise verbs per paragraph is enough to lift the texture of your writing. Overdoing it reads as strained.
3. Specific nouns over general ones
Vague nouns like 'people', 'things', and 'problems' dilute your writing. Replace them with the specific group, concept, or issue you mean.
- People → residents, citizens, commuters, employees, consumers, students (whatever the context demands)
- Things → factors, elements, aspects, considerations
- A big problem → a pressing challenge, a persistent issue
After writing an essay, circle every 'people' and 'thing'. If more than two of each remain, replace the rest with specific nouns. This alone often lifts Lexical Resource by half a band.
4. Spelling and word-formation count here too
Lexical Resource is the criterion that captures spelling mistakes and word-formation errors, such as writing 'goverment' or 'responsability'. These slips are common in timed writing, and while occasional errors are tolerated at higher bands, frequent inaccuracies pull the score down. Reserve a minute at the end to scan for spelling, focusing on the longer, less familiar words you used.
What NOT to do
- Do not memorise a list of 'band 9 vocabulary' to sprinkle in. Examiners spot forced rare words immediately, and misused ones cost you accuracy points.
- Do not use idioms like 'every coin has two sides' or 'a blessing in disguise'. Idioms belong in Speaking, not formal Writing, and they often read as memorised.
- Do not repeat the same word because you know it is correct. Show range by replacing it once or twice with a natural alternative, but never force a synonym that feels wrong.
The fastest way to see where your vocabulary is helping or hurting is to grade an essay and check your Lexical Resource score against the sentence-level feedback. The grader highlights collocation errors and word-choice slips by category, so you can spot your pattern in one submission.