Change these sentences into the passive voice
Part D : Present Perfect tense
16. Pollution from factories has destroyed many lakes and rivers
17. My brother hasn't finished his exercises
18. They have discovered oil at the North Pole
19. Nam's father has just bought another villa
20. We haven't seen her since we left school
16.Many lakes and rivers have been destroyed by pollution from factories
17.My brother’s exercises haven’t been finished
18.Oil has been discovered at the NORTH Pole
19.Another villa has just been bought by Nam’s father
20She hasn’t been seen since we left school
16. Many lakes and rivers have been destroyed by pollution from factories.
17.His exercises haven't been finished by my brother.
18.Oil at the North Pole has been discovered.
19.Another villa has just been bought by Nam's father.
20.She hasn't been seen (by us) since we left school.
Em không chắc chắn câu 20 cho lắm