问题
填空题
2006年5月18日．英美科学家公布了人类第一号染色体的基因测序图，这个染色体是人类“生命之书”中最长也是最后被破解的一章．据报道，第一号染色体中共有2.23亿个碱基对，2.23亿这个数用科学记数法可表示为_________．
答案
2.23×108
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2006年5月18日．英美科学家公布了人类第一号染色体的基因测序图，这个染色体是人类“生命之书”中最长也是最后被破解的一章．据报道，第一号染色体中共有2.23亿个碱基对，2.23亿这个数用科学记数法可表示为_________．
2.23×108
| 完形填空。 | |||
| When you're a preteen, a huge problem might be that you just have to have a new rock-rap CD, 1 your parents won't give you the money for it. I thought life was so 2 when things like this happened-until September 11, 2001. I was in P.E. when the planes hit the World Trade Center and the Pentagon. As soon as I got home and for weeks after, I saw the disaster 3 on TV. Seeing the innocent people running for their 4 as the debris(瓦砾) started coming down the fire and smoke rose out of the 5 brought tears to my eyes. I couldn't help imagining what the people on the 6 and in the buildings were thinking and going through, not 7 what was going on. I admired the courage of the firefighters who rushed in and risked their own lives to 8 others. It tore my heart apart to watch the 9 looks on the faces of so many people who didn't know if their loved ones were dead or alive while 10 in all the debris. Then it 11 me: All my life I had thought mainly of myself. I had it easy in life and had been taking it all for granted. A feeling of coldness 12 down my back, and I cried just thinking of the possibility that it could have easily 13 to my family. My mom or dad could have been killed like that, and I would never, ever see the m again. I began to evaluate what a real 14 in life was. This disaster 15 me that awful things can happen to anyone at any time. Now when my mom or dad or sister go somewhere, even if it's just 16 the store, I try to remember to tell them that I love them because I know there is a 17 that I may never tell them that 18 . Not getting a new CD is not going to make or 19 my life. I can live with those kinds of problems. But losing someone I love would 20 make my life miserable. 9/11 showed me just what I am. | |||
| ( )1. A. but ( )2. A. unbelievable ( )3. A. expand ( )4. A. lives ( )5. A. curtains ( )6. A. seats ( )7. A. believing ( )8. A. join ( )9. A. puzzled ( )10. A. hidden ( )11. A. rewarded ( )12. A. cooled ( )13. A. happened ( )14. A. relationship ( )15. A. taught ( )16. A. on ( )17. A. story ( )18. A. again ( )19. A. end ( )20. A. rather | B. so B. uncomfortable B. occur B. families B. buildings B. planes B. thinking B. save B. severe B. found B. surprised B. dropped B. compared B. problem B. reminded B. in B. doubt B. once B. change B. truly | C. or C. unfair C. strike C. houses C. gates C. corners C. knowing C. meet C. dirty C. placed C. hit C. ran C. related C. need C. persuaded C. at C. chance C. enough C. spare C. probably | D. for D. uncertain D. unfold D. friends D. bedrooms D. streets D. caring D. calm D. desperate D. trapped D. told D. passed D. turned D. fate D. informed D. to D. plan D. ever D. break D. frequently |