11. Human behavior is mostly a product of learning, ______the

　　behavior of animal depends mainly on instinct。

　　A. whereas

　　B. so

　　C. unless

　　D. that

　　12. Mumps ____ a very common disease which usually affects children。

　　A. was

　　B. is

　　C. are

　　D.were

　　13. The _____largest state is, and has been since Alaska's

　　admission into the Union, Califoria。

　　A. three

　　B. third

　　C. first third

　　D. most

　　14. ________ the surface of metal, but also weakens it。

　　A. Not only does rust corrode

　　B. Not only rust corrode

　　C. Rust, which not only corrodes

　　D. Rust not only corrodes

　　15. It's nice to go for a walk __ a summer evening。

　　A. on

　　B. in

　　C. at

　　D. during

　　16. "Are these two issues settled?"

　　"No, they still were _____ conflict."

　　A. during

　　B. on

　　C. with

　　D. in

　　17. "Did the medicine make you feel better?"

　　"No, ______ the worse I feel."

　　A. taking more medicine

　　B. the most medicine I take

　　C. the more medicine I take

　　D. when I take more medicine

　　18. His health is _________。

　　A. as poor, if not poorer than, his sister

　　B. poor as his sisters if not poorer

　　C. as poor as, if not poorer than, his sister's

　　D. as poor, if not poorer than his sister's

　　19. Susanne had worked for three years to be a computer

　　analyst but found her progress ________。

　　A. discouraging and unsatisfied

　　B. discourageable and dissatisfaction

　　C. discouraging an dissatisfaction

　　D. unsatisfactory and discouraging

　　20. That definition leaves _____ for disagreement。

　　A. much room

　　B. a small room

　　C. great deal room

　　D. not so big a room