IELTS Reading: Sentence Completion
Sentence completion tests whether you can find specific information in a passage and fit it grammatically and factually into a given sentence, using words taken directly from the text.
What this question looks like
You are given a set of incomplete sentences that summarise or restate points from the passage, each with a gap. A word limit applies, usually "NO MORE THAN TWO WORDS" or "NO MORE THAN THREE WORDS". You must find the matching information in the text and copy the exact word(s) into the gap, making sure the completed sentence is grammatically correct and matches the meaning of the passage.
Step-by-step approach
- 1Read each incomplete sentence carefully before searching the passage, and underline the key content words (nouns, verbs, qualifiers) so you know exactly what fact or category the gap needs.
- 2Predict the type of word that must fill the gap: is it a noun, a verb, a number, a date, an adjective? This narrows your search and stops you copying the wrong word class.
- 3Scan for synonyms and paraphrases of the sentence's key words in the passage rather than the exact words, since the question is almost never a direct quote of the text.
- 4Read the sentence around the matching part of the passage closely, then test your chosen word by reading the completed sentence back: does it make grammatical sense and does it match the passage's meaning exactly, not just partially?
- 5Check the word limit precisely by counting words, not characters, and remember that hyphenated words usually count as one word while numbers can be written as figures.
- 6Copy spelling exactly from the passage, since spelling mistakes and unnecessary added words (like 'a' or 'the' when not needed) cost you the mark even if the meaning is right.
Worked example
Passage extract: 'Urban beekeeping has grown rapidly in the last decade, but experts warn that rooftop hives placed too close together can lead to overcrowding, forcing bees to travel further to find flowering plants and ultimately reducing honey yields.' Complete the sentence below using NO MORE THAN TWO WORDS from the passage. When rooftop hives are positioned near one another, bees may have to fly ___________ to reach flowers.
further / farther
The sentence in the question paraphrases 'placed too close together' as 'positioned near one another', signalling this is the matching section. The passage states the effect of overcrowding is that bees are 'forcing bees to travel further to find flowering plants'. The gap needs an adverb describing distance travelled, which matches 'travel further' in the text. Only 'further' fits grammatically after 'fly' and stays within the two-word limit, so it is the answer directly lifted from the passage without altering its form.
Try it yourself
Read the short passage and choose the option that correctly completes the sentence using information from the text.
Passage: 'Although coral reefs cover less than one percent of the ocean floor, they support around a quarter of all known marine species. Marine biologists note that this disproportionate richness makes reefs especially vulnerable, since damage to a small area can affect an enormous number of organisms that depend on it for shelter and food.' Complete the sentence: Coral reefs are considered particularly at risk because their small size supports a ___________ number of species. Choose the correct word from the options below.
Common mistakes
- !Writing more words than the limit allows, for example giving 'much further away' when the limit is two words and the passage only needs 'further'.
- !Changing the word form from the passage, such as writing 'reduces' when the sentence grammatically needs 'reduce' or vice versa, which makes the sentence incorrect even though the meaning is right.
- !Choosing a word that matches the topic generally but not the precise fact asked for, because they stopped reading at the first similar-looking phrase instead of confirming the full context.
- !Misspelling a word copied from the passage, which loses the mark even when the correct word has been identified.
- !Ignoring grammatical fit, for example filling a gap that needs a singular noun with a plural one taken directly from the passage.
Quick quiz
1. Why is scanning for exact words from the sentence usually the wrong strategy for sentence completion?
2. A gap requires 'NO MORE THAN TWO WORDS'. The passage says 'a sharp rise in demand'. Which answer is safest if the sentence reads 'Sales increased due to a ___________ in demand'?
3. What should you do immediately after selecting a word to fill a gap?
4. Predicting the required word class (noun, verb, adjective, number) before scanning the passage mainly helps you to:
Practise this in a real IELTS test
Take a free Reading test with expert evaluation and apply the technique under exam conditions.
Take a free Reading testIELTS Reading: Sentence Completion — FAQ
Do sentence completion answers have to be copied exactly from the passage?
Yes, in almost all cases you must use the exact word or words as they appear in the passage, including spelling. You cannot change the word form (for example plural to singular) unless the sentence grammar in the question genuinely calls for a different, still-present form.
What happens if I write more words than the limit allows?
The answer is marked wrong even if the extra words are correct and relevant, because the word limit is a strict rule. Always count your words after writing the answer and remove any articles or extra description that are not part of the exact phrase needed.
How is sentence completion different from summary completion?
Sentence completion gives you a list of separate, standalone sentences based on different parts of the passage, while summary completion asks you to fill several gaps within one continuous paragraph that summarises a specific section. Sentence completion questions can also appear in any order relative to the passage, whereas summary completion gaps usually follow the passage's sequence within that section.