They didn't go to bed _________ they finished the homework last night.
A.when B.after C.until
— Kelly looks like her mother.
— Yes, they ___________ have big eyes.
A.both B.all C.either
— Could you please give me some advice _________how to get good grades?
— I think you should try your best to prepare _________the exam.
A.for ... of B.on ... of C.on ... for
If you have a toothache（牙痛）, you can go to see a _________.
A.doctor B.dentist C.teacher
I usually watch TV _________Saturday evening.
A.on B.in C.at
— Do you want to be _________astronaut when you grow up, Michael?
— No. I want to be _________computer programmer.
A.a …a B.an ... a C.an ... the
