What does TOEFL iBT Build a Sentence ask you to do?
ETS describes Build a Sentence as arranging words or groups of words to produce a grammatically complete sentence or question. The specifications also include partially completed sentences. Start by checking what is already fixed on screen, then review the available segments.
Our method is to form a structural hypothesis before moving anything. Look for a statement, a direct question, or a sentence with a subordinate clause. A question mark does not mean that every part of the sentence must be inverted: the main question can contain a clause that keeps the subject–verb order.
How do you find the core without translating word for word?
Identify the verb forms. A modal takes a base verb; an auxiliary may signal the passive voice or a compound tense. For each finite verb, find the group that could be its subject. Do not automatically choose the nearest noun: a relative clause or complement may separate the subject from its verb.
In “The maps near the entrance show the walking routes,” the subject of “show” is “the maps.” “Near the entrance” tells you where the maps are; it does not control agreement. Temporarily reduce a long sentence to its skeleton, then add the details back. This is a reasoning step: you do not remove any segment from your final answer.
Which segments should stay together?
Assemble strong dependencies before adding details of time or place. “A detailed schedule” is a noun phrase; “during the rehearsal” is a prepositional phrase. A determiner should not be left on its own, and a preposition needs a complement. The segment boundaries may already help you identify these groups.
However, distinguish closeness from rigidity. A time expression may fit in more than one position. If several orders seem possible, return to the context and fixed elements instead of inventing a restriction. For the written exercises below, we give one possible construction and explain what it expresses; this practice does not reproduce the official interface.
How do you handle an indirect question or relative clause?
The words “why,” “whether,” or “that” may mark the start of a dependent clause. Identify what the clause completes. In an indirect question introduced by “why,” the subject normally comes before the verb: “why the meeting ended,” even though the direct question would be “Why did the meeting end?”
A relative clause gives information about a noun. Mentally bracket it to find the main clause: “The photographs [that Maya selected] belong to the archive.” There are two subject–verb relationships: “Maya selected” in the relative clause and “photographs belong” in the main clause. Checking each one helps prevent matching the main verb to a noun inside the relative clause.
Can you explain the two word orders?
This teaching exercise provides a fixed beginning so you can focus on the embedded structure. Write the sentence, then identify which part contains the question. Read the explanation only after you have justified your word order.
Use every group once to make a question. Begin with “Could”. [ why ] [ was changed ] [ could you explain ] [ the shuttle route ]
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The solution, step by step
One correct construction: “Could you explain why the shuttle route was changed?”
The method in action
- The main question is “Could you explain…?” The modal “could” comes before its subject “you,” and the verb “explain” stays in the base form.
- “Why” introduces what needs to be explained. Inside this indirect question, “the shuttle route” comes before “was changed.” The order “why was the shuttle route changed” would belong to a separate direct question.
- “Was changed” is a passive verb phrase: the route is affected by the change. Each group is used once, and no additional auxiliary is needed.
Can you find the subject of the main verb?
The second exercise inserts a clause between the subject and its verb. Do not start by treating all the nouns as one list: first identify what the museum did and what happened to the postcards.
Use every group once. Begin with “The postcards” and describe the postcards that were displayed, not the donor. [ were donated ] [ the museum displayed ] [ by a former student ] [ the postcards ] [ that ]
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The solution, step by step
One possible construction: “The postcards that the museum displayed were donated by a former student.”
The method in action
- The reduced main clause is “The postcards were donated by a former student.” The plural subject “postcards” agrees with “were,” and “by” introduces the person who made the donation.
- The relative clause “that the museum displayed” specifies which postcards are meant. “The museum” is the subject of “displayed”; “that” refers back to the postcards as the object of that verb.
- Placing the relative clause after “student” would change what it describes and no longer answer the prompt. Position therefore affects meaning as well as agreement.
The pitfall
Choosing what sounds right without being able to explain it
A familiar-sounding sequence may hide a misplaced auxiliary or a poorly attached relative clause. Before finishing, name the subject of each verb and the function of each remaining group. If your only explanation is “I’ve heard it before,” revisit the structure.
After reviewing the answer, record a specific cause in your notebook: inversion retained in an indirect question, agreement with the wrong noun, or a complement separated from the word it completes. Then try a different construction that tests the same relationship. Recognizing the corrected sentence is not enough to confirm you understand the mechanism.
Key takeaways
- Read the fixed elements before arranging the segments.
- Identify every subject–verb relationship and keep related groups together.
- Check how subordinate clauses attach to the sentence as well as their grammar.
- This process is our practice method; it does not predict a score.