Complete the Words gives you a paragraph with word endings removed and ten blanks to type. How to read the stem, use context and avoid plural slips.
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Quick answer
Complete the Words shows a short paragraph with the endings of ten words removed. You see the opening letters, for example "mas____", and you type the rest of the word. Each blank is worth one raw point and the ending is checked exactly, so grammar and spelling both count.
What the task looks like on screen
You get a paragraph of roughly 60 to 100 words on a single topic. Ten words in it have been cut in half. What remains on screen is the opening fragment plus a blank: "remar____", "shore____", "poll____". You click each blank and type the letters that finish the word.
You are not choosing from options. There is no list. You produce the ending yourself, which makes this the only production task in the entire Reading section, and the only place where your spelling is directly assessed.
The paragraphs are cohesive, which matters more than it sounds. Every sentence is about the same subject, so the missing words are not random vocabulary items. They belong to a topic, and once you have identified the topic the field of candidates narrows sharply. A paragraph about tide pools will want words like "shorelines", "creatures", "salinity". A paragraph about volcanoes will want "eruptions", "molten", "landscapes". Half the work is done by recognising which world you are in.
Point density is why this task deserves your respect. Ten blanks at one point each means a single paragraph is worth ten raw points. That is more than a full academic passage question set, in a task that takes a fraction of the time. Students who skim it because it looks like a warm-up exercise are giving away the best-value points in the section.
The four clue sources, in the order you should use them
Every blank is solvable from four kinds of evidence. Use them in this order, because the first two are fast and the last two are slow.
1. The visible stem. The letters you can see are a hard constraint. "Pyroc____" can only be "Pyroclastic". "anem____" in a paragraph about rock pools can only be "anemones". Sometimes the stem alone finishes the job, and when it does you should be typing within three seconds.
2. The grammatical slot. Look at what the sentence needs. Is this position a noun, a verb, an adjective? Is the noun singular or plural? Does the verb follow a third person singular subject? This is the step students skip and it accounts for most of their lost points. "The ocean retre____" needs a verb agreeing with a singular subject, so "ats" not "at". "these shallow basi____" needs a plural, so "ns" not "n".
3. The topic field. Read the first sentence properly before you touch any blank. It names the topic, and the topic supplies the vocabulary set. Once you know you are reading about coral reefs, "bleac____" resolves to "bleaching" instantly, where in isolation it might have been "bleached" or "bleacher".
4. Collocation and the surrounding words. English words travel in pairs. "widespread bleaching events", "seismic activity", "environmental variations". If you have a candidate that is grammatically fine but sounds odd next to its neighbour, it is probably wrong.
Notice that none of these four require you to have seen the word before. They require you to use what the sentence has already told you. Students with a modest vocabulary routinely score eight or nine out of ten on this task by working the constraints properly, while stronger readers score six because they trusted the first word that came to mind.
Stem patterns and what they usually want
Stem shape
Typical endings
Worked example
The slip to avoid
Stem ends mid-suffix on an abstract noun
-ation, -ution, -ition
poll____ in a sentence about threats to reefs gives "pollution"
Typing "polluting" when the slot needs a noun after "and".
Stem is a plural noun cut short
-s, -es, -ies, -ns
basi____ after "these shallow" gives "basins"
Typing the singular because the stem looks singular. Let the determiner decide.
Stem is a verb after a singular subject
-s, -es, -ats, -ies
retre____ after "the ocean" gives "retreats"
Typing the bare verb. The subject is singular, so the verb takes -s.
Stem opens an -ing form
-ing, -hing, -ying
bleac____ before "events" gives "bleaching"
Typing "bleached". The word modifies a following noun, so the participle is active.
Stem is an adjective cut short
-ful, -able, -ive, -ous
remar____ before "small ecosystems" gives "remarkable"
Typing a noun form. Check what the word is describing.
Stem is a person or agent noun
-ists, -ers, -ors
Scien____ before "study these communities" gives "Scientists"
Typing the singular when the verb has no -s, which tells you the subject is plural.
Common opening fragments and the endings they most often take in this task. Never apply these blind. Check the grammar of the slot first, then choose.
The routine: 90 seconds per paragraph
1
Read the whole paragraph once, ignoring the blanks
Fifteen seconds. Do not stop at a blank, do not try to solve anything. You are establishing the topic and the register. Students who start solving at the first blank end up re-reading the paragraph three times.
2
Fill the blanks you know instantly
Thirty seconds. Sweep the paragraph and type every ending that arrives without effort. Usually five or six of the ten. Do not stop to admire them and do not check them yet.
3
Work the remaining blanks with the grammar test
Thirty seconds. For each one left, say out loud in your head what the slot needs: plural noun, third person verb, adjective. Then find the word that fits both the stem and the slot. This is where the points that separate a six from a nine live.
4
Guess anything still empty
Ten seconds. Nothing is deducted. If "endu____" will not resolve, type "re" and move on. A guess constrained by the stem and the topic is right far more often than students expect, and a blank is right zero percent of the time.
5
Read the paragraph back at speed with your answers in place
Five seconds. You are listening for one thing only: a word that sounds wrong in its sentence. This final pass catches the plural and tense slips that cost most students two points per paragraph.
Type it: the migration paragraph
This is the paragraph analysed just below, but you type it rather than read it. Do it first. The analysis underneath goes blank by blank, and it is worth far more once you have already committed to an answer and can see which of your instincts were right. Press Enter to jump to the next blank.
Migrating birds navigate across continents with astonishing accur. Some species rely on the position of the sun, while others detect the Earth's magn field. Young birds often follow experienced adults, learn the route through repetition. Coastal constru and artificial lighting now interfere with these ancient migra, leaving exhausted flocks far from their usual feed grounds.
Six blanks here rather than the ten a real paragraph carries, because this one exists to be taken apart. The full-length version is at the end of the lesson.
A worked paragraph
Here is a paragraph in the style of the task. Work it before you read the analysis.
Migrating birds navigate across continents with astonishing accur____. Some species rely on the position of the sun, while others detect the Earth's magn____ field. Young birds often follow experienced adults, learn____ the route through repetition. Coastal constru____ and artificial lighting now interfere with these ancient migra____, leaving exhausted flocks far from their usual feed____ grounds.
The answers are "accuracy", "magnetic", "learning", "construction", "migrations", "feeding". Now the reasoning, because the reasoning is the transferable part.
accur____ follows "with astonishing", so the slot needs a noun. "accurate" is an adjective and would not sit after "astonishing". The ending is "acy".
magn____ sits between "the Earth's" and "field", so it must be an adjective describing "field". "magnetism" is a noun and fails the slot. The ending is "etic".
learn____ opens a participle clause after a comma, describing how young birds follow adults. That structure wants "-ing". "learned" would give a past tense verb with no subject, which breaks the sentence.
constru____ is one half of a compound subject with "artificial lighting", and the verb is "interfere". A noun is needed, so "construction". Students who type "constructing" here have read the meaning correctly and produced an ungrammatical sentence.
migra____ follows "these ancient", which forces a plural. "migration" scores zero. The ending is "tions".
feed____ modifies "grounds", so it is a participle used adjectivally: "feeding grounds". This is also a fixed collocation, which is a second, independent reason to be confident.
Six blanks, and in five of them the grammar of the slot did more work than the vocabulary did. That is the pattern. If you are losing points here, the odds are strongly that you are a competent reader who is not checking the slot.
Complete the Words checklist
Read the first sentence properly. It gives you the topic, and the topic gives you the vocabulary set.
Type the ending only. Never the whole word.
Before typing, name the slot: plural noun, third person verb, adjective, participle.
Let determiners decide number. "these", "many", "several" force a plural.
Let the subject decide the verb ending. A singular subject takes -s.
Check collocations. "seismic activity" and "feeding grounds" are fixed pairs, and a word that breaks the pair is usually wrong.
Fill every blank before you leave the paragraph. Nothing is deducted for a wrong guess.
Read back once with your answers in place, listening for anything that sounds off.
Practice: five blanks, five reasons
Each question gives you a sentence in the style of the task. Pick the correct ending. The explanations tell you which constraint decided it, which is the part you carry into the exam.
Deep beneath the surface, hydrothermal vents support communities that survive without sunlight. Dense colonies of tube worms cluster around the openings, where superheated water carries dissolved min____ from the crust.
What ending completes the blank correctly?
"carries dissolved min____" has no determiner and no singular article, and "dissolved" modifies a mass or plural noun here. "minerals" is the form that fits, and it is the standard collocation with "dissolved". The ending is "erals"."mineral" would need an article, as in "a dissolved mineral". Without one the singular count noun is ungrammatical, which is exactly the slot check that catches this error."mineralize" is a verb. The slot follows "carries" and is the object of that verb, so it must be a noun. A verb here gives you two verbs and no object."mineralogy" is the study of minerals, an abstract field. Water does not carry a field of study, and the sentence is describing physical material from the crust.
The monsoon shapes life across much of South Asia. Each summer, warm air rises over the heated landmass and draws moist air inland from the sea. When that moisture rea____ the mountains, it cools and falls as rain.
What ending completes the blank correctly?
The subject of the clause is "that moisture", which is singular, and the sentence is in the present tense throughout ("rises", "draws", "cools", "falls"). A present tense verb with a singular subject takes -es here, giving "reaches"."reach" is the bare form. It would be correct with a plural subject, but "that moisture" is singular, so the verb needs the -es ending."reached" is past tense, and every other verb in the paragraph is present. Mixing tenses inside a description of a recurring seasonal pattern breaks the sentence."reaching" gives a participle with no auxiliary verb, leaving the "When" clause without a finite verb. The clause would never resolve into a sentence.
Medieval cathedrals took generations to build. Stonemasons trained for years before they were trusted with load-bearing work, and the most skilled among them carved the intricate decor____ elements that still draw visitors today.
What ending completes the blank correctly?
The blank sits between "intricate" and "elements", so it is describing "elements". That slot needs an adjective, and "decorative" is the adjective form. The ending is "ative"."decoration" is a noun. Placing a noun between an adjective and another noun gives "intricate decoration elements", which is not English."decorations" fails for the same reason as the singular, and adds a number mismatch on top: the head noun of the phrase is already "elements"."decorate" is a verb. The sentence already has its verb, "carved", so a second finite verb inside the object phrase makes the sentence collapse.
Antarctic ice cores preserve a record of the atmosphere going back hundreds of thousands of years. Researchers drill deep into the sheet and extract cylinders of ice, then measure the tiny air bubbles trapped inside. These bubbles allow scien____ to reconstruct past carbon dioxide levels with remarkable precision.
What ending completes the blank correctly?
"allow scien____ to reconstruct" needs a plural noun as the object, matching the plural subject "These bubbles" and the general statement being made. The passage has already used "Researchers", confirming the plural framing. The ending is "tists"."scientist" is singular and would need an article, as in "allow a scientist to". The sentence has no article, so the singular is ungrammatical."scientific" is an adjective. "allow scientific to reconstruct" has no object for "allow" at all, so the structure fails immediately."science" is an abstract noun and cannot be the subject of "to reconstruct" in this construction. Science does not reconstruct anything, people do.
Urban planners increasingly treat street trees as infrastructure rather than ornament. A mature canopy lowers surface temperatures, absorbs rainfall before it overwhelms drains, and filters particulate matter from the air. Cities that neglect their trees end up paying for the same benefits through expensive engineer____ solutions.
What ending completes the blank correctly?
"engineering solutions" is the intended phrase, an attributive use of the -ing form describing the kind of solution. It is also a fixed collocation in this register, which is a second reason to be confident. The ending is "ing"."engineered solutions" is grammatical English, but the sentence is contrasting natural infrastructure with the built alternative as a category. In context, and against the collocation, the -ing form is what this slot wants."engineers solutions" puts a plural person noun in front of another noun, which does not form a compound here. It would read as a verb phrase with no subject."engineeree" is not a word. This option exists to catch students who match the stem letters without asking whether the result is real English.
Exam length: ten blanks, ninety seconds
A real paragraph carries ten blanks worth ten raw points, which is more than a whole academic passage question set. Put ninety seconds on your phone and run the routine from earlier in this lesson: read it through once ignoring the gaps, sweep the ones you know, then work the rest with the grammar test. Guess anything still empty before you check.
Cities are consist warmer than the country around them, a pattern known as the urban heat island. Dark surfaces such as asphalt abs sunlight during the day and release it slowly after sunset, so the diffe is often greatest at night. Tall build trap this heat by redu airflow, and air conditioning pushes still more warmth into the street. The effect is not unif across a city: neighborh with mature trees are several degrees cooler than districts with none, which is why planting is now trea as public health policy rather than land.
Check where your losses sat. If they were words you did not know, that is a vocabulary gap and it is slow to close. If they were words you did know but typed in the wrong form, a plural for a singular or a noun where the slot wanted an adjective, that is the grammar test not being applied, and that is a fortnight of work rather than months. Almost everybody finds the second kind.
How to practise this task in ten minutes a day
Take any short factual paragraph, from a news article, a textbook, a Wikipedia introduction. Cover the last half of every eighth word with your thumb or delete it in a text editor. Then restore the endings from memory and check.
Do it on topics you find dull, not topics you enjoy. The test will not ask you about football. It will ask you about tide pools, pyroclastic flows, and campus recycling schemes. Reading exclusively about things that interest you leaves exactly the vocabulary gaps this task probes.
When you get one wrong, write down which of the four clue sources would have saved you: the stem, the grammar slot, the topic, or the collocation. After two weeks you will find the same source keeps appearing. Almost everyone has one weak channel, and once you know yours, you can check for it deliberately during the test.
One final note on speed. The target is roughly 90 seconds per ten-blank paragraph. If you are taking three minutes, you are almost certainly solving the blanks in the order they appear rather than sweeping the easy ones first. Reordering your attack is worth more here than any amount of extra vocabulary.
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10 more sections in this lesson
You have read the opening. The rest covers the method in full, with worked examples and practice questions that explain why each wrong answer is wrong.
All 45 lessons: Reading, Listening, Writing and Speaking
Real exam audio and record-yourself speaking drills
Just the ending. If the screen shows "gar____" and the answer is "garden", you type "den". Typing the whole word produces a wrong answer.
Each blank is one raw point, and a paragraph typically has ten blanks. One paragraph is therefore worth ten raw points, more than a full academic passage question set.
Yes. The ending is checked exactly. A correct word with a misspelled or wrongly inflected ending scores zero, which is why the grammar check before you type matters so much.
Always. Nothing is deducted for a wrong answer, and a guess constrained by the visible stem and the paragraph topic succeeds far more often than students expect.
Use the grammar of the slot to choose. Ask what the sentence needs there: a plural noun, a third person verb, an adjective. In practice the slot almost always eliminates one of the candidates outright.
About 90 seconds. Read it once ignoring the blanks, sweep the easy ones, work the rest with the grammar test, guess anything left, then read back once listening for a word that sounds wrong.