`11` Why wasn't the accident reported sooner?

`-` S + V2/V-ed

`->` bđ : S + was/were + ( not ) + V-II + ( by O )

`12` Someone could be heard crying in the next room

`-` S + could + V-inf

`->` bđ : S + could + be + V-II + ( by O )

`13` The car was seen to drive up outside the police station by Jáck

`-` S + V2/V-ed

`->` bđ : S + was/were + V-II + ( by O )

`14` They were overheard to say that they didn't really like the food

`->` S + V2/V-ed

`->` bđ : S + was/were + V-II + ( by O )

`15` I expect your money to be found somewhere in your bedroom

`->` S + expect + sth + to be + V-II

`16` English has just been begun tobe learned by Jane for 2 weeks

`->` S + has/have + V-II

`->` bđ : S + has/have + been + V-II + ( by O )

`17` Facebook is continued to use as a main way of socializing

`->` S + V(s/es) 

`->` S + am/is/are + V-II + ( by O )

`18` They are going to have someone repair the roof

`->` have sb to do sth : nhờ ai làm gì

`19` You are supposed to type the report before the meeting

`->` It’s your duty do sth `->` You are supposed to do sth

`20` I suggested that the matter should be put to the committee

`->` suggested + V-ing `=` suggested + that + S + ( should ) + V-inf

`->` bđ : S + suggested + S + should + be + v-II

`21`  Everyone is supposed to collect litter in public areas

`->` It’s your duty do sth `->` You are supposed to do sth

$baoyen.$