Duolingo English Test Fill in the Blank: Format and Tips

One sentence, one unfinished word, 20 seconds: how the task works and is scored, plus 15 practice sentences with answers and explanations.

Lume Test

May 20, 2026

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5 min read

Duolingo English Test Fill in the Blank: Format and Tips

Key Takeaways

One sentence, one unfinished word, 20 seconds: how the task works and is scored, plus 15 practice sentences with answers and explanations.

Fill in the Blanks is one of the shortest tasks on the Duolingo English Test. You read one sentence, one word in it is unfinished, and you type the missing letters before a 20-second timer runs out. This guide explains what the screen shows, how many of these questions you will meet, how they are scored and which subscores they feed. Then you can try 15 practice sentences in the same format, with answers and explanations.

Fill in the Blanks is a separate task from Interactive Reading. If you have seen a passage where you pick each missing word from a list of options, that is part of Interactive Reading, not this task. In Fill in the Blanks there is no list and no passage: you type the end of one word in one sentence.

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What Is the Duolingo English Test Fill in the Blanks Question?

The on-screen direction is “Complete the sentence with the correct word.” You read a sentence with one unfinished word. The beginning of the word is already shown, and you type the missing letters to complete it.

The sentences come from many kinds of writing, such as stories, textbooks, news articles, personal writing and conversations, so expect everyday and academic vocabulary side by side.

The task is adaptive, which means the difficulty of the sentences you see can change as the test goes on. If one sentence feels much harder than the last, that is normal.

Fill in the Blanks at a Glance

What you see	One sentence with one unfinished word; the beginning of the word is shown
What you do	Type the missing letters to complete the word
Time	20 seconds per question
How many	6–9 questions per test
Scoring	Right or wrong; the word must be spelled correctly
Subscores	Reading, which also counts toward Literacy and Comprehension

Sources: Duolingo English Test Official Guide 2026, pages 11–12; Duolingo English Test Scoring Guide for Teachers 2026, sections 2.6 and 3.2; Duolingo English Test Help Center articles “Fill in the Blanks” and “Test Structure”.

How Fill in the Blanks Is Scored

Each question is marked right or wrong, and you must spell the word correctly to get it right. A word with one wrong letter does not earn the point.

Guessing costs you nothing extra. Duolingo says you will not be penalized more for entering an incorrect answer than for skipping a question, so always type your best attempt before the timer ends.

The task is graded automatically: your response is compared with the correct response.

Your results count toward the Reading subscore. Reading is also half of two combined subscores: Literacy is the average of Reading and Writing, and Comprehension is the average of Reading and Listening. Like the overall score, every subscore is reported on a scale from 10 to 160.

How to Answer a Fill in the Blanks Question in 20 Seconds

Read the Whole Sentence First

Duolingo’s own advice is to read the whole sentence before you focus on the unfinished word. The words after the gap often decide the answer. In “She was too tir_ _ to finish the race”, the pattern “too … to” tells you an adjective is needed, so the word is tired.

Let the Letters You Have Narrow the Word

The beginning of the word is your biggest clue. Think of the words that start with those letters, keep the ones that fit the meaning of the sentence, then check which one fits the grammar. In the practice items below, each underscore stands for one missing letter.

Check the Grammar Around the Gap

Look at the words right before and after the gap. A singular subject in the present simple needs -s on the verb. “Has” or “have” before the gap points to a past participle such as improved. A number such as “fifty” points to a plural noun. After “very” or “too”, check what the word describes: a noun needs an adjective (very quiet), a verb needs an adverb (very quickly).

Think in Collocations

Collocations are words that are commonly used together, such as “conduct research”, “heavy rain” or “reach a decision”. If you see “take a deep bre_ _ _”, the collocation makes breath the obvious answer. Learning common pairs like these gives you more clues to work with on this task.

Spell Carefully, Then Move On

Because the word must be spelled correctly, check the ending before you continue: -ance or -ence, -able or -ible, a single or double consonant. With only 20 seconds per question, do not spend that time changing an answer you are already fairly sure of.

Worked Example

Sentence: “Regular exercise can lower your blood pre_ _ _ _ _ and improve your sleep.”

Step 1, read the whole sentence: “lower your blood ___” needs a noun, something that can go up or down.

Step 2, use the letters and collocations: the word starts with p-r-e, and “blood pressure” is a common pair. “Presence” has the same length but makes no sense here.

Step 3, spell it: p-r-e-s-s-u-r-e, with a double s. The answer is pressure.

Practice Questions for Duolingo Fill in the Blanks

Each sentence has one unfinished word, and each underscore stands for one missing letter. Give yourself 20 seconds per sentence, write the full word, then check your answers in the next section.

The three levels are our own grouping to help you build up step by step. Duolingo does not label its questions this way, and in the real test the difficulty adapts to your answers.

Level 1: Everyday Sentences

Please turn off your phone before the film beg_ _ _.
My sister drinks a glass of wa_ _ _ every morning before breakfast.
We took an umbrella because the forecast said it would ra_ _ in the afternoon.
The library is very qui_ _, so students go there to study.
He forgot his keys, so he could not open the fro_ _ door of his house.

Level 2: Study and Work

The company plans to hire fifty new emp_ _ _ _ _ _ next year.
Turning off the lights when you leave a room can red_ _ _ your electricity bill.
After months of practice, her pronunciation has impr_ _ _ _ a lot.
The bridge was closed for repairs, so drivers had to take a long det_ _ _.
Many people moved to the city in search of better job opp_ _ _ _ _ _ _ _ _ _.

Level 3: Academic and News Style

The debate in parliament lasted several hours before a final deci_ _ _ _ was reached.
Although the evidence was limited, the researchers remained opti_ _ _ _ _ _ about the results of the trial.
The museum keeps its oldest manuscripts behind glass because they are too frag_ _ _ to be handled.
Critics argued that the report’s conclusions were not sup_ _ _ _ _ _ by the data it presented.
Because the instructions were ambig_ _ _ _, half of the participants completed the task incorrectly.

Answers and Explanations

begins (beg + ins). The subject “the film” is singular, and after “before” English uses the present simple even for a future event. “Begged” also starts with b-e-g but makes no sense here.
water (wa + ter). “A glass of” needs something you can drink. “Waste” has the same length but does not fit the meaning.
rain (ra + in). “It would” is followed by a base verb, and the umbrella tells you what the weather will be.
quiet (qui + et). “Very” needs an adjective, and the second half of the sentence gives the reason. Do not confuse quiet with quite.
front (fro + nt). “Front door” is a fixed pair of words. Frost, frown and froze start the same way but do not fit.
employees (emp + loyees). “Fifty” needs a plural noun, and a company hires employees. “Employers” has the same length, which makes it the trap; check the meaning before you type.
reduce (red + uce). “Can” is followed by a base verb, and turning off lights makes a bill smaller.
improved (impr + oved). “Has” plus a past participle forms the present perfect, so the word needs the -ed ending.
detour (det + our). You “take a detour” when a road is closed. “Detail” starts the same way but makes no sense.
opportunities (opp + ortunities). “Job opportunities” is a common pair, and the ten missing letters give the plural form. Watch the spelling: double p, then -ities.
decision (deci + sion). “A final ___ was reached” needs a noun, and you “reach a decision”.
optimistic (opti + mistic). “Remained” is followed by an adjective. “Although” sets up a contrast: the evidence was weak, yet the researchers stayed positive.
fragile (frag + ile). “Too ___ to be handled” needs an adjective meaning easily damaged.
supported (sup + ported). “Were not ___ by” is a passive form, so the word is a past participle; conclusions are “supported by data”.
ambiguous (ambig + uous). Instructions that cause mistakes are unclear. Check the ending: -uous, not -ous.

Common Mistakes to Avoid

Ignoring the letters on screen: a word can fit the meaning and still be wrong because it does not start with the letters you are given. “A glass of wa_ _ _” cannot be juice or milk.

Dropping the ending: -s, -ed and -ly carry the grammar. “Her pronunciation has improve” is wrong; “has improved” is right.

Singular and plural slips: ask whether the noun can be counted. Countable nouns take a plural after words like “many” or “fifty”, and we say fewer people but less water.

Spelling slips: the word must be spelled correctly, so one wrong or missing letter loses the question. Words like necessary, environment and accommodation are worth practising.

Making it more complicated than necessary: the right answer is often a common, simple word. Not every gap hides an advanced term.

Leaving it blank: Duolingo does not penalize a wrong answer more than a skipped one, so a reasonable guess is always worth typing.

How to Improve Your Fill in the Blanks Skills Fast

The Method of “Active Recall”

When you meet a new word while reading, try to work out its meaning from the context before you look it up. The next day, cover the word, look only at its first two or three letters and try to recall the whole word, just as the task asks you to. Then use it in three sentences of your own, trying a different word form where one exists, for example decide, decision and decisive.

Practise Word Endings

Keep a list of endings that change a word’s class: -tion and -ment for nouns, -ive, -ous and -able for adjectives, -ly for adverbs. When you know which class the gap needs, the right ending follows.

Read the Same Kinds of Text the Test Uses

Fill in the Blanks sentences come from stories, textbooks, news articles, personal writing and conversations. Reading a little from each of these every day gives you the vocabulary range the task draws on.

Best Resources to Practice Fill in the Blanks Questions

Duolingo Official Practice Test: Duolingo offers a free practice test that you can take as many times as you want. Duolingo notes that it is shorter than the certified test, is not proctored, and gives a score range that is only an estimate, less accurate than the real test. Use it to get used to the interface and the timer.

Duolingo English Test Help Center: the official Fill in the Blanks article shows the question screen and the keyboard controls, for example using the arrow keys or TAB to move between blank spaces.

Conclusion

Fill in the Blanks rewards three habits: read the whole sentence, use the letters you are given together with the grammar around the gap, and spell the full word correctly within 20 seconds. Work through the 15 sentences above against the clock, note which ones you missed and why, then try them again a few days later.

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