change of voice — active to passive covering present continuous and past continuous,

 

. "The teacher is explaining the grammar rules." (Present Continuous)
A. The grammar rules were being explained by the teacher.
B. The grammar rules had been explained by the teacher.
C. The grammar rules are being explained by the teacher.
D. The grammar rules have been explained by the teacher.

2. "The workers were demolishing the old factory." (Past Continuous)
A. The old factory was demolished by the workers.
B. The old factory was being demolished by the workers.
C. The old factory had been demolished by the workers.
D. The old factory has been demolished by the workers.

3. "The chef is preparing a special dish for the guests." (Present Continuous)
A. A special dish was being prepared for the guests by the chef.
B. A special dish had been prepared for the guests by the chef.
C. A special dish has been prepared for the guests by the chef.
D. A special dish is being prepared for the guests by the chef.

4. "The students were solving a difficult math problem." (Past Continuous)
A. A difficult math problem has been solved by the students.
B. A difficult math problem is being solved by the students.
C. A difficult math problem was being solved by the students.
D. A difficult math problem had been solved by the students.

5. "The journalist is interviewing a famous actor." (Present Continuous)
A. A famous actor was being interviewed by the journalist.
B. A famous actor is being interviewed by the journalist.
C. A famous actor has been interviewed by the journalist.
D. A famous actor had been interviewed by the journalist.

6. "The engineers were testing the new machine." (Past Continuous)
A. The new machine has been tested by the engineers.
B. The new machine had been tested by the engineers.
C. The new machine is being tested by the engineers.
D. The new machine was being tested by the engineers.

7. "The children are decorating the classroom for the festival." (Present Continuous)
A. The classroom is being decorated by the children for the festival.
B. The classroom was being decorated by the children for the festival.
C. The classroom has been decorated by the children for the festival.
D. The classroom had been decorated by the children for the festival.

8. "The doctors were treating the injured victims." (Past Continuous)
A. The injured victims are being treated by the doctors.
B. The injured victims have been treated by the doctors.
C. The injured victims were being treated by the doctors.
D. The injured victims had been treated by the doctors.

9. "The company is offering a big discount to its customers." (Present Continuous)
A. A big discount was being offered to its customers by the company.
B. A big discount had been offered to its customers by the company.
C. A big discount is being offered to its customers by the company.
D. A big discount has been offered to its customers by the company.

10. "The police were questioning the witnesses at the station." (Past Continuous)
A. The witnesses were being questioned by the police at the station.
B. The witnesses had been questioned by the police at the station.
C. The witnesses have been questioned by the police at the station.
D. The witnesses are being questioned by the police at the station.

---

Answer Key

1. C
2. B
3. D
4. C
5. B
6. D
7. A
8. C
9. C
10. A