Dưới đây là các câu đã được chuyển sang dạng bị động:

18. My mother had been preparing meal.
=> Meal had been being prepared by my mother.

19. Our teacher is teaching us.
=> We are being taught by our teacher.

20. He will be writing a novel at this time tomorrow.
=> A novel will be being written by him at this time tomorrow.

21. They have been eating lunch since 11:30.
=> Lunch has been being eaten since 11:30.

22. He is bringing her a nice present.
=> She is being brought a nice present by him.

23. We have been waiting for our boss since early morning.
=> Our boss has been being waited for (by us) since early morning.

24. The sheep were eating grass on the meadow.
=> Grass was being eaten by the sheep on the meadow.