18．It is obvious to the students ______ they should get well prepared for their future.

A. as　　 　　B. which　　 　　　　C. whether　　 　　　D. that

17．I’m sorry you’ve been waiting so long， but it’ll still be some time ____ Brian gets back.

A. before　 　B. since　 C. till　 D. after　

16．The house I grew up ________ has been taken down and replaced by an office building.

A. in it　　　 B. in　　　 C. in that　　　 D. in which

15．I invited Mary and Jane to dinner, but 　　　　of them came.

　　　 A．none　　 　　　　　 B．either　　 　　　　　 C．both　　 　　　　　　 D．neither

14．The plant is dead . I ________ it more water.

　　 A. will give　　 B. would have given　 C. must give　　 D. should have given

13．The fact has worried many scientists ______ the earth is becoming warmer and warmer these years.

A. what　　　　　 　　B. which　　　　 　　C. that　　　 　　　　D. though

12．He has ______ little education that he finds it impossible for him to equal ______ important a task.

　　 A. so ;such　　 B. such ; so　　　 C. so ;so　　　 D. such ; such

11．China is playing an important role in the world. That’s 　　　Laura has come to study Chinese.

　　　 A．because　　 　　 B．why　　 　　　　　 C．how　　 　　　　　 D．that

10．My friend showed me round the town, 　　　　was very kind of him.　

A. which　　　　 　　B. that　　　　 　　　C. where　　　　 　　D. it　

9. -----How did you find your visit to Mountain Tai, John ?

　 ----- _________.

A. Oh ,wonderful indeed.　　　　 B. I went there alone .

C. First by train and then by ship.　 D. A guide showed me the way .