ex.213

1. is examined, was examined, is being examined

2. was tested, is tested, was being tested

3. is answered, will be answered, was answered, was being answered

4. is cooked, will be cooked, was cooked

5. is used, was used, will be used, was being used

6. is written, will be written, was written, is being written, has been written

7. is taught, is being taught, will be taught, was taught  

ex.215

1. is cut

2. is being cut

3. is being painted

4. is painted

5. are repaired

6. are being repaired

ex.217

1. Do you know who spoilt it?

2. Do you know who damaged it?

3. Do you know who ate it?

4. Do you know who drank it?

5. Do you know who scratched it?

6. Do you know who tore it?

7. Do you know who cut it?

8. Do you know who locked it?

9. Do you know who changed it?

10. Do you know who brought it?