Answer:
The sentences rewritten in the passive voice are:
a) A question will be asked by her.
b) The experiment was being explained by the tutor.
c) Our homework has been done by us.
Explanation:
The first thing we need to understand about passive voice is that it emphasizes the receiver of the action expressed by the verb. Thus, what is the object of the verb in the active voice becomes the subject in the passive voice. In the sentences we are changing here, they are "a question", "the experiment" and "our homework".
The second point is that the verb tense must not be changed from one voice to the other. All we do is add "to be" as an auxiliary verb, according to the original tense. We also use the main verb in its past participle form. In the sentences we are changing here, this is how it happens:
a. will ask --> will be asked
b. was explaining --> was being explained
c. have done --> has been done
Finally, what is the subject in the active voice becomes the agent of the passive voice, following "by". With that in mind, we can change the sentences:
a) She will ask a question. - A question will be asked by her.
b) The tutor was explaining the experiment. - The experiment was being explained by the tutor.
c) We have done our homework. - Our homework has been done by us.
