There is n’t any difference between the two.I really don’t know __________.
Ａ.what to choose B. which to choose
C. to choose what D. to choose which
The students were ____ over the ____ problem, listening to the teacher with a ____
expression on their faces.
| A．puzzled; puzzling; puzzling | B．puzzled; puzzling; puzzled |
| C．puzzling; puzzling; puzzled | D．puzzling; puzzled; puzzling |
---Would you mind my sitting here ____ lunch? ---______.
A. and have, No, not at all C. and having, No, thank you.
C. to have, Never, go ahead. D. and have, Oh, it’s my pleasure.
It was rude ______ you to stare at the foreigner when he passed by just now.
| A．of | B．for | C．with | D．to |
The reason for his success is ______ he has worked very hard.
| A．why | B．that | C．whether | D．how |
—Where is Bob? I cannot find him anywhere.
—He have been off long. I heard him make a call just now.
| A．shouldn’t | B．can’t | C．mustn’t | D．needn’t |