I/

1.fixed

2.finished

3.done

4.be given

5.hasn't been used

II/

1.Must / be finished by us before 10?

2.haven't been explained by our teacher.

3.should be cleaned by us twice a day.

4.Have/been stolen by the thieves in the national museum?

5.has been destroyed by the fire.

E1:

1. be fixed

2. be finished

3. been done

4. be given

5. isn't used

E2.

1. Must the test be finished before ten?

2.The english grammar has not been explained by our teachers.

3. Our teeth should be cleaned twice a day.

4. Has the most valuable painting be stolen in the national museum?

5. Many houses have been destroyed by the fire.