Question

Choose the most appropriate passive form for given sentence:
Who taught her French?
A. By whom was she taught French?
B. Who is that who teach her French?
C. Who is teaching her French?
D. Whom has taught French to her?

Answer 1

Hint:When converting active voice into passive voice the structure of a sentence are object + auxiliary verb+ past participle + by subject. Only in interrogative sentence starting with "who" , the passive voice starts with "whom".

Complete step-by-step answer:
There are rules which is to be followed while converting active into passive voice that are :
*The object changes into subject.
*Addition of auxiliary verb
*Addition of preposition "by"
*Verb changes into past participles of the verb.
In Option A, "who" is changed into "By whom" and the subject verb changes into the object verb by subject. Since, taught is already a past tense addition of was/were take place with the past participle. It fulfills all the rules of passive voice. Therefore Option A that is (By whom was she taught French?) is a correct option and most appropriate passive form of the given sentence.
Option B is who is that who teach her French is an incorrect option because here who does not change into whom and it does not comply with the rules of passive voice.
Option C is Who is teaching her French is an incorrect option because who is not changed into who and also it is not in past participle whereas the given sentence is in past participle. Option D is Whom has taught French to her is an incorrect option because here the subject is not converted into object and the preposition by is also not there.

Note:WH interrogative sentences in active voice starts with WH in passive voice. Sentences with " Who" are the only interrogative sentence which is converted into "whom" in passive voice.