12. -I'm going to the post office.

　　-____you're there,can you get me some stamps?

　　A. As B. While C. Because D. If (1999)

　　13. ____you've got a chance,you might as well make full use of it.

　　A. Now that B. After C. Although D. As soon as

　　14. You should make it a rule to leave things ___you can find them again.

　　A. when B. where C. then D. there

　　15. We'll have to finish the job,______. (1999)

　　A. long it takes however B. it takes however long C. long however it takes D. however long it takes

　　16. The WTO cannot live up to its name ______it does not include a country that is home to one fifth of mankind.(2000)

　　A. as long as B. while C. if D. even though

　　17. It is generally believed that teaching is _____it is a science.

　　A. an art much as B. much an art as C. as an art much D. as much an art as

　　18. A computer can only do ____you have instructed it to do.

　　A. how B. after C. what D. when

　　19. John shut everybody out of the kitchen _____he could prepare his grand surprise for the party.

　　A. which B. when C. so that D. if

　　20. The mother didn't know_____to blame for the broken glass as it happened while she was out.

　　A. who B. when C. how D. what

　　21. Don't be afraid of asking for help_____it is needed.

　　A. unless B. since C. although D. when

　　22. A fast food restaurant is the place,_____,just as the name suggests,eating is performed quickly.

　　A. which B. where C. there D. what

　　Part B：Put the following into English.