Answer:1) The briefcases are made of plastic by them.
2) My daughter was stung by a bee this morning.
3) Why wasn't the road repaired by them?
4) Children under sixteen aren't admitted by them.
5) The door was locked by them,Boone can open it now.
1) You will be told by somebody how to get there.
2)Our summer house was broken into by burglars.
3) For his fifth birthday, a toy train was given to him by them.
4) I was promised a higher salary by them.
5) I shall be taught two foreign languages in this college by them.
6) The auditorium was filled with smoke.
7) She was offered a better position by them.
8) We are being followed by someone.
10) She was asked very personal questions in the interview by them.
11) He was prescribed some tranquilizers by the doctors.
12) The boy was always laughed at by them.
13) He was handed a large envelope by someone.
14) You ought to be paid twenty pounds by them.
15) He was given an injection by one of the nurses.
16) He was denied admittance to the casino by them.
17) We have been offered excellent condition by them.
18) A doctor was sent for immediately by them.
19) Several provinces were granted political autonomy by the government.
20) The boy was showed some tricks by them.
Explanation: The passive voice is used when the person or thing denoted by the subject is the receiver of the action (that is, when the subject is passive or is acted upon).
The passive voice is used when the subject of the active voice is unknown, unimportant or vague, (e.g; people, they, somebody, a person).
I hope this helps.