chuyển thành câ bị động: 1.they were building a new school here when we came 2. he will send his parents a gift 3. She has bought two new dresses recently

`1,` A new school was being built here when we came.

`->` Bị động của thì quá khứ tiếp diễn

Cấu trúc:

S + was/were + being + Ved/V3 + (by + O) +...

`2,` `→` His parents  will be sent a gift.

`→` A gift will be sent to his parents.

Cấu trúc:

C1: `S_1 +` Be + P.P `+ O_2` (gián tiếp) + (by + O)

C2: `S_2 +` Be + P.P + to/for + `O_1` (trực tiếp) + (by + O)

`3,` Two new dresses have been bought recently.

`⇒` Bị động thì hiện tại hoàn thành

Cấu trúc:

S + have/has + been + P.P + (by + O) + ...