完形填空。 Most of us can remember the days when we didn't use e-mail as an everyday vehicle for communication. Slowly but surely, it crept (慢慢移动) into 1 . E-mail is a 2 tool for college students at any level. It's available 24 hours a day,7 days a week and 3 at holidays. Most universities assign students an account entrance, 4 there is usually not even an option (选择) involved. You can do everything from consulting on homework and projects, 5 classmates, family and friends, and getting daily new services to 6 you informed of world 7 . But, what are the 8 ? E-mail can be e-jail. You might 9 hours writing and replying to e-mails 10 you should be busy with the books for an upcoming exam. 11 ,you might be signed up for so many daily services, 12 horoscopes (占星术), new services, or personals, that your mailbox is so 13 'junk mail',that finding the 14 e-mails through your box might take hours. If you're a student, 15 is precious. Create and organize your e-mail folders into important school-related mail, correspondence (通信)with friends and family, and a folder for jokes, horoscopes and other new services. 16 put the mail into the proper folders first, and when you've finished, head for the important school-related folder first. Respond to the most important e-mails first and, 17 you have time, you can get to the others. 18 your friends from forwarding those tiresome jokes, tiresome quizzes, and chain mails. The minute you 19 you've got one, delete it 20 so you won't be tempted to read it. (     )1. A. the lives (     )2. A. valuable (     )3. A. even (     )4. A. but (     )5. A. keeping touch with (     )6. A.keeping (     )7. A. accidents (     )8. A. advantages  takes (     )9. A. spend (     )10. A. for (     )11. A. Otherwise (     )12. A. such as (     )13. A. full up with (     )14. A. important (     )15. A.money (     )16. A.Sometimes (     )17. A. if (     )18. A. Encourage (     )19. A.examine (     )20. A.later B. life B. changeable B. still B. so B. getting touched to B. keep B. incidents B. mistakes B. cost B. because B. Or B. such like B. full B. necessary B. mark B. Always B. although B. Watch B. check up B. immediately C. our lives C. favorable C. ever C. because C. losing touch with C. leaving C. events C. wrongs C. take C. since C. But C. for example C. filled up with C. practical C. grade C. Almost C. since C. Discourage C. find C. after D. us life D. usable D. yet D. except that D. keeping in touch with D. leave D. things D. disadvantages D. pay D. when D. However D. so as D. fill with D. possible D. time D. Usually D. because D. Refuse D. realize D. soon