Chuyển sang câu bị động: Someone has taken my book away

chuyển sang câu bị động: 
 

18. Someone has taken my book away.

-> My book ___________________________________

19. He didn't help me with my homework.

-> I ___________________________________________

20. We have learnt English for three years.

-> English ______________________________________

21. My father often reads books before bedtime .

-> Books ............................................................................

22. Lan bought some comic books for her brother .

-> Some comic books ..........................................................

23. My sister received a letter yesterday .

-> A letter ............................................................................

24. She can solve the problem in just 2 minutes .

-> The problem .....................................................................

25. Nowadays people use electricity for lighting.

-> Electricity ...........................................................................