21. They wondered how to use that support service.
22. Mai asked her mother when to turn off the oven
23. Phong and Minh could not decide where to park their bikes
24. He was not sure whether to call her then
25. They wondered what to do to make Linh feel happier
26. Could you tell me where to sign my name?
27. I have no idea when to leave for the bus
28. We are not sure where to hang the paiting
29. They can not decide who to go first
30. He wondered how to tell this news to his parents
CHÚC BẠN HỌC TỐT NHA! NHỚ CHO MIK 5 SAO VÀ CÂU TLHN NỮA NHA!!!