I don’t know _______________.
--- When will you return to your hometown? ---__________.
Only ________ of the students come to school by bus.
It is selfless ________ the doctor to devote all the time he had ________ for the patients.
--- is the school from your home, do you know?--- About 30 minutes’ walk.
---How long have you ________ your penfriend?---For five days. I received it last Sunday.