19.＿＿＿several times about it,but he could not give the correct answer.

A.Being asked　　　　　　　 B.Having been asked

C.He would ask　　　　　　 D.He had been asked

18.There is plenty of rain in the south ＿＿ there is little in the north.

A.while　　　　 B.as　　　　 C.when　　　　 D.so

17.＿＿＿air is to man,so is water to fish.

A.Since　　　　 B.Just　 　　　C.Like　　　　 D.As

16.The students of the music school study ＿＿＿＿.

A.music but also some other subjects

B.some other subjects as well as music

C.music as well as some other subjects

D.some other subjects and music

15.What the doctors really doubt is＿＿＿＿my mother will recover from the serious disease soon.

A.when　　　 B.how　　　 C.whether　　　 D.what

14.Information has been put forward＿＿＿more middle school graduates will be admitted into universities.

A.while　　　 B.that　　　 C.when　　　 D.as

13.He’s got himself into a dangerous situation＿＿＿he is likely to lose control over the plane.

A.where　　　 B.which　　　 C.while　　　 D.why

12.＿＿＿＿is known to everyone,the moon travels round the earth once every month.

A.It　　　　 B.As　　　　 C.That　　　　 D.What

11.After ten years,she changed a lot and looked different from＿＿＿she used to be.

A.that　　　　 B.whom　　　　 C.what　　　　 D.who

10.Recently I bought an ancient Chinese vase,＿＿＿＿was very reasonable.

A.which price　　　　　 B.the price of which

C.its price　　　　　　　 D.the price of that