Build a Sentence's word bank almost always includes at least one decoy — a word that looks plausible but is grammatically wrong for the sentence. Recognizing the specific trap patterns ETS uses makes them much easier to spot quickly.
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The most common trap: a verb in the wrong tense or form sitting next to the correct one ("knew" vs. "know," "going" vs. "gone"). These are spelled correctly and look natural in isolation, which is exactly why they're easy to pick under time pressure — always check the verb form matches the sentence's actual tense, not just that it's a real word.
A second common pattern: a word from the same root but the wrong part of speech for its position ("decision" the noun vs. "decide" the verb, "quickly" the adverb vs. "quick" the adjective). These traps rely on the words looking related enough that a fast reader picks the familiar-sounding one without checking whether it actually functions correctly in that specific slot.
A subtler trap: two words that mean roughly the same thing but require different sentence structures ("make" vs. "let" with different following grammar, "suggest" vs. "recommend" with different preposition patterns). These require actually knowing the grammatical pattern each word takes, not just its meaning — this is the trap type most worth deliberate practice, since word-order intuition alone doesn't reliably catch it.
Practice Build a Sentence items with detailed explanations of each trap.