`Answer + Explai n :` 

`1.` It was said by him that he was a doctor.

`->` Bị động : It tobe (am/is/are (was/were) said that `+` `S_2` `+` `V_2` `+` `O_2`

`2.` Our written work was returned to us by the teacher.

`-` Cấu trúc câu bị động thì QKĐ

`->` S `+` was/were `+` V3/ed `+` ( by `+` O )

`@` Lưu ý :

`->` I/ He/ She/ It / Danh từ số ít / Danh từ không đếm được `+` was `+` V3/ed

`->` We/ You/ They/ Danh từ số nhiều `+` were `+` V3/ed

`-` Work `->` Danh từ số ít `->` dùng was 

`3.` Her report had been finished by noon.

`-` Cấu trúc bị động thì QKHT :

`->` S `+` had `+` been `+` V`3`/ed

`4.` It is thought by people that she is a pilot.

`->` Bị động : It is thought that `+` S `+` V

`5.` Five suspects have been arrested by the police.

`-` Cấu trúc bị động thì HTHT :

`->` S `+` have/has `+` been `+` V`3`/ed

`@` Lưu ý :

`->` He/ She/ It/ Danh từ số ít / Danh từ không đếm được `+` has + V`3`

`->` I/ We/ You/ They/ Danh từ số nhiều `+` have `+` V`3`

`-` Suspects`->` Danh từ số nhiều `->` dùng have

S1 + V1 + that + S2 + V2 

→ S2 + be + V3/ed (V1) + to + V1 (cùng thì)

→ S2 + be + V3/ed (V1) + to have + V3/ed (khác thì)

→ It is + V3/ed (V1) + that + S2 +V2

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Bị động - các thì:

- Thì QKĐ: S + was/were + V3/ed 

- Thì QKHT: S + had been + V3/ed 

- Thì HTHT: S + has/have + been + V3/ed 

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1. He was said to be a doctor.

2. Our written work was returned to us by the teacher,

3, Her report had been finished by noon.

4. She is thought to be a pilot.

5. Five suspects have been arrested by the police.

`color{orange}{~LeAiFuRuiHuiBao~}`