Fill in the Blanks

One sentence with one word cut in half. You are given the opening letters and have twenty seconds to type the rest. Spelling must be exact, so this is a vocabulary test and a spelling test at once.

The Facts

Time20 seconds per sentence
Preparation timeNone
How many per test6-9 sentences, one set
SubscoreReading
AdaptiveYes
Scored asRight or wrong

What You See

A single sentence with one damaged word in it. The letters you are given are always the beginning of the word, and the remaining letters are shown as empty boxes, so you know exactly how many letters are missing. Backspace works. Continue moves you on.

The damaged words are adjectives, adverbs, nouns and verbs — never function words. The sentences are drawn from stories, coursebooks, news, personal writing and conversation, so register varies from one item to the next.

The Method That Works

Twenty seconds is enough for a sequence, not for a hunt. Use the same three steps every time and the item stops being about inspiration.

  1. Identify the part of speech first. What comes before the blank usually settles it. After the or a, a noun. After very or quite, an adjective. After will or to, a verb.
  2. Count the boxes. The letter count eliminates most candidates instantly. de___ with three missing is delay, not delivery.
  3. Read the rest of the sentence for the semantic clue. These sentences almost always contain a synonym, an antonym or a collocation that fixes the meaning.

The three steps on one item

  • Sentence: Heavy rain caused a serious de___ in the delivery of the equipment.
  • Step 1: after a serious, this is a noun.
  • Step 2: de plus three letters — five letters total.
  • Step 3: caused and in the delivery point at something that stops things arriving on time.
  • Answer: delay.

Why Collocation Matters More Than Vocabulary

A surprising number of these items are not testing whether you know a word, but whether you know which word goes with the words around it. Keep a detailed rec____ is record because keep a record is a fixed phrase, not because record is difficult.

  • Learn verbs with their objects: make a decision, reach a conclusion, raise a concern.
  • Learn adjectives with their nouns: serious delay, detailed record, heavy rain.
  • Learn nouns with their prepositions: a delay in, an increase in, a reason for.

When the sentence gives you a fixed phrase, the letter count is usually confirmation rather than a clue. When it does not, the letter count is the clue.

Common Mistakes

  • Typing a word that fits the meaning but not the letter count. Check the boxes before you commit.
  • Getting the word right and the spelling wrong. This scores zero, which makes spelling drills as valuable as vocabulary drills.
  • Forgetting the word form. She kept a detailed record needs the noun, not recorded.
  • Reading the sentence twice. Twenty seconds does not survive it. Read once, classify, count, type.

How to Practise

  1. Take any article, cover the second half of ten content words, and restore them under a twenty-second clock each.
  2. Keep a misspelling list and retest it weekly. On this test spelling errors are wrong answers, not style points.
  3. Drill word families: analyse, analysis, analytical, analyst. One family covers several possible blanks.
  4. Practise the sets on the Reading samples page with the answer key closed.
Kirill O'Nayd, Duolingo English Test expert

Written by Kirill O'Nayd

English test expert and educator at TestSucceed, where he builds the Duolingo English Test practice tasks and mock tests and has spent years taking apart how computer-adaptive, AI-graded exams award their points. See all TestSucceed preparation materials.

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