Identify the correct grammatical structure for each sentence and explain why.

Here are the answers to the questions:

24. The students B. were expelled from school because they did not perform well. Explanation: The sentence requires a passive voice verb in the past tense to indicate that the students were the recipients of the action.

25. Nobody A. did they a hero. Explanation: This is a tag question. "Nobody" makes the main clause negative, so the tag must be positive. "Did they" is the most appropriate positive tag among the options, implying a past action or general statement.

26. The teacher B. who taught us last year has moved to another school. Explanation: "Teacher" is a person, and "who" is the correct relative pronoun