Free ACT Sentence Structure and Formation practice questionsEnhanced ACT, 2026 format
Fragments, run-ons, misplaced modifiers, and faulty parallelism inside an underlined portion of a passage, judged by what makes the sentence most grammatically acceptable.
Answer each question, then read why the right answer is right and why the tempting one is wrong.
Question 1
English
Hiking along the ridge at dawn, the valley below revealed a blanket of fog that hid the river entirely. Only the church steeple pierced the gray.
Which choice makes the sentence most grammatically acceptable?
Question 2
English
[2] The librarian who started it, Aurelia Sandoval, had not intended to build a collection. She wanted to give away a surplus of tomato seed from her own garden. Because word spread quickly, and by the second spring the drawers held forty-one varieties. Most had come back from borrowers, which meant that most had been grown in Ashmont soil at least once.
Which choice makes the sentence most grammatically acceptable?
Question 3
English
[3] The features have names, and the names are instructions. A pillow is water piling up on the upstream side of a submerged rock. A hole is the recirculating water on the downstream side, where the current falls over the rock, and turns back on itself. An eddy is the calm pocket behind an obstruction, where the water runs upstream and a boat can rest.
Which choice makes the sentence most grammatically acceptable?
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