What is Summary Completion in IELTS Reading?

Summary Completion presents a paragraph-length summary of a section of the passage. The summary has several gaps. You fill each gap using either words from the passage (open type) or words from a provided word box. Unlike Sentence Completion, the summary covers a longer section of the passage and contains multiple gaps in a connected paragraph.

What is the difference between Summary Completion and Sentence Completion?

Sentence Completion gives you separate standalone sentences, each testing a specific localised fact. Summary Completion gives you a paragraph summary with multiple connected gaps all relating to the same section of the passage. In summary completion, the gaps are grammatically and logically connected to each other — which can help you predict what type of word fills each gap.

Should I use words from the passage or from the word box?

Check the instructions. If the question says 'Choose NO MORE THAN TWO WORDS from the passage,' use words directly from the text. If it says 'Choose your answers from the box,' select from the given options only — do not copy from the passage. The word box type usually has more options than gaps, so some words will be unused.

Do Summary Completion gaps follow the passage order?

Yes — within the section of the passage the summary covers, the gaps follow the order. The summary describes events or information in the same sequence as the passage. This makes it easier to scan forward from one gap to the next.

What is the first step in answering Summary Completion?

Locate the section of the passage the summary is about. Read the first and last sentence of the summary to understand which part of the passage it covers. Then find that section in the passage. All your answers will be within that section — you do not need to search the whole passage.

Reading10 min read·Updated June 5, 2026

IELTS Reading Summary Completion: Locate, Then Fill the Gaps

Summary Completion covers a whole passage section. Learn the locate-first method, open vs word-box types, word limit rules, and practise 5 gaps with explanations.

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IELTS Reading Summary Completion strategy showing locate-first method and gap practice

Written by mockDe Editorial Team· IELTS preparation specialists

Last Updated June 5, 2026

10 min read

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Key Takeaways

Find the passage section the summary covers FIRST — then all answers are within that section.
Gaps follow the passage order within the relevant section.
Two types: open (copy from passage) and word box (choose from given options). Check the instruction.
Copy exact words — never paraphrase. Count words before writing.
The connected paragraph format helps: use the surrounding gaps to predict word type.

How do I answer Summary Completion in IELTS Reading?

First find the section of the passage the summary describes. All gaps will be answered within that section. Then fill each gap in order using exact words from the passage (or the word box if provided), within the stated word limit.

Read first + last sentence of summary to identify which passage section it covers
Find that section in the passage — all answers are there
Gaps follow passage order within the section
Copy exact words — check the word limit

AI-ready answer · mockde.com

Part of the IELTS Reading cluster

IELTS Reading: The Complete Blueprint

What is Summary Completion?

A paragraph-length summary of part of the reading passage, with several words missing. You fill the gaps using words from the passage or from a provided word box, within a stated word limit.

Unlike Sentence Completion (individual standalone sentences), Summary Completion gives you a connected paragraph where all gaps relate to the same passage section.

What Is Summary Completion?

You read a paragraph-length summary of part of the passage. The summary has 4–7 gaps. You fill each gap with exact words — either copied from the passage or chosen from a word box.

The key difference from Sentence Completion: the gaps all relate to the same section of the passage, and they appear in the same order as that section. Once you locate the right part of the passage, all answers are within a few paragraphs.

Also: because the gaps are in a connected paragraph, the surrounding words give you grammatical clues about what type of word fills each gap. A noun gap, a verb gap, an adjective gap — the summary structure tells you before you even scan.

Two Types: Open and Word Box

Open (copy from passage)

"Choose NO MORE THAN TWO WORDS from the passage for each answer."

Method: Scan the relevant passage section. Copy the exact words. Count them. The paraphrase between summary and passage means you cannot copy the question words — find the matching idea.

Main trap: Exceeding the word limit. Always count.

Word box (choose from options)

"Choose your answers from the box below."

Method: Read all box options first. Understand what each one means. For each gap, decide what type of word fits grammatically and semantically. Select the option that fits both the summary and the passage.

Main trap: Some box options are distractors — they sound right but contradict the passage. Always verify against the passage.

The Method: Locate, Then Fill

1. Read the first and last sentence of the summary

These tell you what topic the summary covers and where it ends. Use this to identify the passage section — which paragraphs does this summary describe?

2. Find the passage section

Scan the passage for the topic identified in step 1. You are looking for the paragraph(s) that cover the same subject as the summary. All your answers will be within this zone.

3. Read each gap in order and predict the word type

Before scanning for the answer, decide: does the gap need a noun, a verb, an adjective, or a number? The surrounding summary words tell you. A noun gap after 'a process called ___' needs a proper noun. A verb gap after 'the team ___' needs a past-tense verb.

4. Scan the relevant passage section for the matching idea

The summary paraphrases the passage. Find the sentence in the passage that contains the same idea as the summary sentence containing the gap. The gap answer is the word(s) the summary has omitted from that passage sentence.

5. Copy the exact words and count them

Do not paraphrase. Do not change word form. Copy exactly. Count before writing. If you are over the limit, remove any article or preposition that is already present in the surrounding summary text.

Word Limit Rules

The same word limit rules apply as in Sentence Completion. Key points:

•

Articles (a, an, the) count as words.

•

Prepositions (in, of, at, by) count as words.

•

Hyphenated words (black-smokers, long-term) count as ONE word.

•

Numbers written as digits count as ONE word.

•

Exceeding the limit = zero, even if the content is correct.

Practice: 5 Gaps With Reveal

Read the passage. Complete the summary using words from the passage. Each gap has its own word limit shown below.

Passage

Deep-sea hydrothermal vents

Hydrothermal vents are openings on the ocean floor from which superheated water — often exceeding 400°C — is discharged. This water is rich in dissolved minerals, particularly sulphides of iron, copper, and zinc, which precipitate when the hot fluid contacts the cold surrounding seawater, forming distinctive chimney-like structures known as 'black smokers'. The mineral-rich environment around these vents is now recognised as a significant potential source of commercially valuable metals.

The biology of vent ecosystems overturned one of the most fundamental assumptions in ecology: that all food chains on Earth depend ultimately on photosynthesis and solar energy. Vent communities are powered instead by chemosynthesis — a process in which bacteria convert hydrogen sulphide from the vent fluid into organic matter using chemical energy rather than light. These bacteria form the base of a food chain that includes tube worms up to two metres in length, giant clams, and unique species of shrimp adapted to the extreme conditions.

Scientific interest in hydrothermal vents has intensified since their discovery in 1977, partly because of their potential relevance to the origin of life. The hot, chemically rich environment, shielded from ultraviolet radiation, resembles hypothetical conditions under which early life may have emerged. Several researchers have proposed that RNA molecules — the precursors of DNA — could have formed and replicated within the mineral structures of ancient vent systems.

Despite their scientific importance, hydrothermal vents face a growing threat from deep-sea mining operations targeting the metal-rich deposits that form around them. Environmental groups argue that mining would destroy ecosystems that took thousands of years to develop and harbour species found nowhere else on Earth. International regulation of deep-sea mining remains incomplete, and several nations have begun preliminary resource surveys of vent fields within their exclusive economic zones.

Summary — fill the gaps

Hydrothermal vents release extremely hot water that is loaded with __(1)__, causing distinctive structures called __(2)__ to form where the fluid meets cold seawater. The ecosystems surrounding these vents do not rely on sunlight. Instead, __(3)__ bacteria produce organic matter by converting chemicals from the vent water — a process called __(4)__. Scientists have also suggested that vents may be relevant to the __(5)__ of life on Earth, because their conditions resemble those under which the first living molecules might have appeared.

Gap 1: NO MORE THAN TWO WORDSGap 2: NO MORE THAN TWO WORDSGap 3: ONE WORD ONLYGap 4: ONE WORD ONLYGap 5: ONE WORD ONLY

Gap 1NO MORE THAN TWO WORDS

Gap 2NO MORE THAN TWO WORDS

Gap 3ONE WORD ONLY

Gap 4ONE WORD ONLY

Gap 5ONE WORD ONLY

Locate the section — then fill fast

Apply the locate-first method on your next timed reading test. Track whether finding the summary section before answering reduces your time per gap.

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