—How many students are there in the classroom?
—_____ I don’t know where they have gone.
A.No one. B.None. C.Nobody. D.Nothing.
The rubbish _____ is produced every day is becoming a serious problem in cities around the world.
A. what B.that C.who D.whose
More and more trees were cut down. _____, many animals are dying out.
A.In the end B.So that C.As a result D.At last
We should often keep _____ touch with each other, because we are good friends.
A.on B.to C.in D.up
—Do you think a radio is useful in learning English?
—Sure. A radio can _____ listening English songs and reports.
A.be used by B.be used as
C.be used for D.be used to
—Do you know _____?
—Sorry, I don’t know.
A.what’s the population of Japan
B.what the population of France is
C.how much of the population of Japan is
D.how many is the population of France