1 Trees must be watered by us every day.
2 This radio can be ment by him.
3 They should not be allowed to work at night.
4 Dictionaries are used by them in the exam.
5 The classroom must be cleaned by the students every day.
6 Some trees were planted on the hill by the boys yesterday.
7 The work can be finished by himself in two days.
8 The business letters are written in English by them.
9 Is his car often ment by him?
10 Was a new house built by you last year?
11 A new TV set wasn't bought by my sister last week.
12 Must it be paid for by me at once?