—Is this your bicycle, David? —No, it's not . It's Helen's.
Lily has ________ homework and she really doesn’t know ________ first.
--- Excuse me, sir. Smoking ________ in the hospital.---Oh, I’m really sorry.
--- How do you like the program The Voice of China?--- ________ amazing program it is! Many people like to watch it.
Dear students, please read every sentence carefully. _______ you are, ________ mistakes you’ll make.
---________ Tom ________ Bob has passed the exam.---Yes. Both of them did quite well.