`8` The articles which customers have bought during the sale cannot be exchanged 

`9` This man mustn't be moved, he's too ill

`10` When this street has been widened, the residents will be kept awake all night by the roar of the traffic 

`=` When they have widened this street, the residents will be kept awake all night by the roar of the traffic 

`=` When this street has been widened, the roar of the traffic will keep residents awake all night

`12` The accident ought to have been reported to the police

`13` It must be dry-clean

`14` After that they should be returned 

`15` He will have to be left here 

Cấu trúc

`->` S + tobe + Vpp (+ by sb)...

@newspacelucy

`8,` Articles which customers have bought during the sale cannot be exchanged.

`9,` This man mustn't be moved; he's too ill.

`10,` When this street has been widened, the roar of the traffic will keep residents awake all night.

`-` Câu bị động HTHT: S `+` have/has `+` been `+` V3/V-ed..(by `+` O) 

`11,` The accident ought to have been reported to the police.

`12,` It must be dry-cleaned.

`13,` After that, they must be returned.

`14,` He'll have to be left here.

`----`

`-` Câu bị động của đtkt:

`-` S `+` đtkt(must/can/have to) `+` be `+` V3/V-ed…(by `+` O)

 ${\text{Lưu ý: }}$

`+` Các đại từ bất định như somebody, nobody, people,..  không dùng by + O