1could you tell me how i can go to the nearest hospital?
2we don't know how to help him
3have you decided where to spend your holidays?
4i have no idea when i can have a sports meet
5i saw the boys who were playing football on the playground
6do you hear someone who is knocking at the door?
7i hope to pass the exam this time
8ask him what is his age.
9i don't know what to do
10i don't know how to get the station
11they want to know where to go.
12they saw an old man running after the dog in the street.
13we heard someone singing in the next room
14we found him a good boy.
15i don't know which sweater to choose.(这句只能在从句中变成简单句)