Answer:
1. She was made a princess by her.
2. The bike was repaired by the mechanic.
3. The dinner was being prepared by her.
4. Were the chocolates being made by her?
5. The letter had been written by me.
6. The lecture was given by her.
7. The seminar was attended by them.
8. My work had been done (by me).
Explanation:
In grammar, the voice is the relationship between the action or state expressed by the verb and the participants of the sentence, such as the subject, object, and others. There are two voices in English:
You can see some rules about the conversion from the active into passive voice below.