`1.` They made him surrender his passport.

- Bị động thì QKĐ

-  S + was/were + VII + by +O.

2. They have now proved this scientific theory to be false.

- Bị động thì HTHT

- S + have/has + been + VII + by + O.

3. They are now salvaging the ca which was blown over the cliff yesterday.

- Bị động thì HTTD

- S + am/is/are  + being + VII + by + O

4. The police are guarding the house where the dead man was found to prevent it from being entered and the evidence interfered with.

- Bị động thì HTTD

- S + am/is/are  + being + VII + by + O

5. Why didn't they either lock or put this car into the garage?

- Bị động thì QKĐ

- S + was/were + VII + by +O.

1. They made him surrender his passport.

2. They have now proved this scientific theory to be false.

3. They are now salvaging the ca which was blown over the cliff yesterday.

4. The police are guarding the house where the dead man was found to prevent it from being entered and the evidence interfered with.

5. Why didn't they either lock or put this car into the garage?

*GT: - Bị động thì QKĐ: S + was/were + VII + by +O.

        - Bị động thì HTTD: S + am/is/are  + being + VII + by + O.

        - Bị động thì HTHT: S + have/has + been + VII + by + O.