One's life has value（）one brings value to the life of others.
| A． | so that | B． | no matter how | C． | as long as | D． | except that |
The question is ______ it is worth doing.
| A．if | B．whether | C．which | D．what |
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 |