Exercise1: Chuyển sang dạng câu bị động 1. We know that you were in town on the might of the crime => 2. They think that your father was a spy in the World Was II => 3. We belive that he has special knowledge which may be useful to the police => 4. You need't have done this =>

1 we know that you were in town on the might of the crime

=>you are known to be in town on the night of the crime.

2 they think that your father was a spy in the World Was II

=>father is thought to be  a spy in the World Was 

3 We belive that he has special knowledge which may be useful to the police 

=> We belive that he has special knowledge which may be useful to the police 

4 You need't have done this

=> This needn't doing