Build a Sentence opens the Writing section. Someone says a short line, and you complete the reply by placing word tiles into blanks around a few fixed words. There is nothing to invent and nothing to type — every point comes from choosing the right tiles and putting them in the one order English grammar allows.
Each item is a two-line exchange. The first line sets the scene — a friend mentions a broken heater, a classmate asks about a club meeting. The second line is your reply, and most of it is missing: a few words are printed in place, and between or around them sit empty slots. Below the reply is a bank of tiles, each holding a single word or a short phrase such as the repair or every year.
You fill every slot, using each tile at most once, until the reply reads as one complete, natural sentence. In some items one tile has no place at all. That extra tile is deliberate: it is usually a near-copy of a tile you do need — does beside is, went beside been, helps beside help — and choosing between the two is the real question.
Because the ten items are scored by fixed logic rather than by a rater, the safest assumption is that a reply has to match an accepted arrangement to count. The upside is that the task rewards a repeatable method. The grammar it draws on is a fairly stable set: question word order, embedded questions, subject–verb agreement, verb patterns after particular words, modifier placement, relative clauses and conditionals.
Build a Sentence is a grammar task in disguise. It checks whether you can control the structures that hold a spoken English reply together:
The printed words are your strongest clue, and they are the part of the sentence you cannot move. A reply that starts with Have you… has already chosen the present perfect for you. One that ends …last night? has ruled out a perfect tense. A tag such as …, didn’t she? tells you the statement before it is past simple with no helper verb.
Before you touch a tile, decide what kind of sentence you are building: a yes/no question, a wh- question, a statement with a tag, a sentence opening with a negative word like Never or Rarely, or a statement that contains a question. Once the frame is clear, most tiles have only one possible home.
In direct questions, the biggest single source of errors is pairing the wrong auxiliary with the main verb. The rule is short: match the helper to the verb form. Be goes with an -ing verb, have/has/had with a past participle (or be, when the sentence is passive), and do/does/did or a modal with the bare base form. So if the only verb tile is taking, the question is Which museum are you taking her to?, however natural do you sounds.
Two exceptions save time. When the question word is itself the subject — Who made the soup? — nothing moves and no do appears. And when be is the main verb, it moves in front of the subject on its own: Is the café open?, never Does the café be open?
Polite replies often wrap a question inside a frame such as Do you know…, Could you tell me… or I wonder…. The frame does the asking, so the part after the question word is a statement: subject, then verb. Do you know where the box office is? is right; where is the box office after the frame is the classic trap, and it sounds convincing precisely because it is how the direct question begins.
Two consequences follow. Any do, does or did that belonged to the direct question disappears, and its tense or -s moves onto the main verb (what time the museum closes). And a yes/no question needs if or whether to join the frame. Keep a whole wh- phrase together at the front, too: how long the tunnel is, not how the tunnel is long.
Long subjects hide their main noun. In the number of swimmers, the head is number, so the verb is has; in each of the rooms, the head is each, so it is has its own. Your ear will pull you toward the noun sitting next to the verb, which is exactly where the extra tile waits.
The same habit works for verb patterns: look at the word before the gap, not the word after it. Worth takes an -ing form, have to takes a base verb, want takes a person plus to, and make or let take a person plus a bare verb. When two tiles are twins — to join and joining, is and are — test each against its controller.
When a reply has two clauses, locate the join — the place for who, that, what, if or so that. A link word printed in the middle tells you exactly where the first part ends. Build the main clause first, because it sets what the second needs: will in the result means a present verb after if; would means a past one; so that calls for a subject plus can or could. Inside the second clause, keep statement order and check agreement with the noun the link word refers to.
Finish every item by naming why the unused tile does not fit. If you can say “does only builds a direct question” or “will be cannot go in an if-clause”, your arrangement is probably right. If you cannot name the reason, rebuild. Some items have no extra tile at all, so never force a tile in just to use it, and never discard one on sight.
Most lost points on this task come from a handful of patterns. Each one below pairs the tempting arrangement with the correct reply.
Mistake: Do you know where is the campus gym?
Better: Do you know where the campus gym is?
Why: The frame Do you know already asks. The embedded part uses statement order: subject, then verb.
Mistake: Which café do you meeting Tomás at?
Better: Which café are you meeting Tomás at?
Why: An -ing verb needs be. Do only helps a base verb, so the do tile is the extra one.
Mistake: Each of the buses have its own guide.
Better: Each of the buses has its own guide.
Why: The head of the subject is each, which is singular. Buses only names the group.
Mistake: What will you do if will the roads be closed?
Better: What will you do if the roads are closed?
Why: Only the main clause takes question order, and an if-clause about the future uses the present tense.
Mistake: The museum is worth to visit.
Better: The museum is worth visiting.
Why: Worth behaves like a preposition, so an -ing form follows it.
Mistake: Has Lena gone to the jazz club last night?
Better: Did Lena go to the jazz club last night?
Why: Last night names a time that is over, which calls for the simple past with did rather than a perfect form.
Two items from our free practice bank. The first has an extra tile that belongs to the direct-question version of the reply; the second has no extra tile, so the challenge is agreement inside a long subject.
Arrange the words and phrases to complete the response. Fill every blank and use each tile no more than once.
Did they mention how long the repair is going to take?
After 'Did they mention', the question about duration becomes an embedded question, so it keeps statement order: 'how long' + subject 'the repair' + 'is going' + the fixed 'to take?'. The tile 'does' is not used. 'How long does the repair take' is direct-question order and cannot combine with 'going'; 'how long is the repair going to take' also inverts the verb and subject inside the embedded clause, which standard English does not allow after 'mention'.
Structure: Did they mention + [how long] + [the repair] + [is going] + to take? Embedded wh-clause in statement order; 'does' is surplus.
Arrange the words and phrases to complete the response. Fill every blank and use each tile no more than once.
Do you know whether each of the rooms has its own bathroom?
After 'Do you know', a yes/no question is embedded with 'whether' and keeps statement order: 'whether' + subject + verb. The subject is 'each of the rooms', so the fixed word 'of' must sit between 'each' and 'the rooms'. Because the head of the subject is 'each', the verb is singular 'has', and the possessive that refers back to it is 'its' ('its own bathroom'). No other placement works: 'its' needs a noun or 'own' after it, and 'the' must come directly before 'rooms'.
Structure: Do you know + [whether] + [each] of [the rooms] + [has] + [its] own bathroom? Singular 'each' controls 'has' and 'its'.
Our free Build a Sentence practice page has all 24 sets (24 questions) from the same bank as the examples above, with answer checking and an explanation for every option. For a short mixed session each day, try the Writing questions of the day.
The strategies on this page come from the Build a Sentence module of the Test Ninjas TOEFL course. Each lesson teaches the English behind the task, then drills it:
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