Answer:

1. Their windows are decorated for the holiday season by shopkeepers.

2. Old buildings are renovated to preserve history by the council.

3. Their essays are submitted by the end of the week by students.

4. New animals are introduced to the public by the zoo.

5. A new piece is performed by the orchestra every month.

CT câu bị động:

S + am/is/are + Ved/V3 + by + O + time.

By luôn đứng sau trạng từ chỉ nơi chốn và đứng trước trạng từ chỉ thời gian.

Nếu trong câu có chỉ đại từ bất định như people, he, she,... thì ta có thể bỏ.

Chúc bạn học tốt

16. Their windows are decorated for the holiday reason (by shopkeepers).

17. Old buildings are renovated to preserve history (by the council).

18. Their essays are submitted (by students) by the end of the week.

19. New animals are introduced to the public (by the zoo).

20. A new piece is performed (by the orchestra) every month.

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- Bị động thì hiện tại đơn: S + is/am/are + PII ( by O )

- N (số ít) + is , N (số nhiều) + are , I + am