Impersonal Passive

`1.`

`->`  It is said that Ha Long Bay consists of about two thousand islands.

`->` Ha Long Bay is said to consist of about two thousand islands.

`2.`

`->` It was thought that the temple had been destroyed by a fire.

`->` The temple was thought to have been destroyed by a fire.

`3.`

`->` It has been reported that there was an accident on the road to Sa Pa.

`->` There has been reported to be an accident on the road to Sa Pa.

`4.`

`->` It is expected that the park will be recognized as a World Heritage Site by UNESCO next year.

`->`  The park is expected to be recognized as a World Heritage Site by UNESCO next year.

`5.` 

`->` It is believed that Son Doong Cave is one of the largest caves in the world.

`->`  Son Doong Cave is believed to be one of the largest caves in the world.

`6.` 

`->` It is believed that twenty large trees were cut down last week.

`->` Twenty large trees are believed to have been cut down last week.

`=============`

`***` Bị động tường thuật :

`-` Chủ động : S + say/belive/think/know/expect/report + that + S + V + O

`=` It is + said/believed/thought/knew/expected/reported + that + S + V + O.

`=` S + be + said/believed/thought/knew/expected/reported + to do/to be doing/ to have done.