Pleasant music is often played_____classes to make students refreshed and relaxed for a while.
| A．between | B．among | C．over | D．after |
The book isn't intended for general readers probably because the author _______ too many scientific terms(术语) in it.
| A．wrote | B．employed | C．analyzed | D．introduced |
---- What does P．O．_________?
----Poster order, I guess．
| A．call for | B．fall for |
| C．prepare for | D．stand for |
It was not until dark __________ he found __________he thought was the correct way to solve the problem．
| A．that; what | B．that; that |
| C．when; what | D．when; that |
It is reported that the United States uses ________ energy as the whole of Europe.
| A．as twice | B．twice much |
| C．twice much as | D．twice as much |
--May I put my bicycle here?
-- Yes. But you should always keep it ________, in case it is stolen.
| A．in relief | B．in sight | C．in turn | D．in return |