填空。 If you are the best of the class. In the last few exams, one or two even several students 1 higher marks than you. 2 do you think about this? Are you jealous of them? Or are you 3 them? Please think it 4 after reading the following passage.You will probably learn 5 . Once a zoologist (动物学家) 6 antelopes (羚羊) which were living on both sides of a river in the Republic of South Africa.He discovered that the antelopes on the east side multiplied (繁殖) more quickly and ran faster than 7 on the west. The zoologist 8 after long,deep thought about the difference,as two groups of antelopes lived in the same environment and they 9 same kind of grass.One year 10 the help of the Animal Protecting Society, he caught ten antelopes on each side and exchanged them. A year later,the ten antelopes sent to the west bank multiplied by fourteen while only three of the ones sent to the east remained. Where are 11 seven? They had been 12 by wolves. At last the zoologist understood why the antelopes on the east were stronger.That was 13 on the east side there were living a group of wolves ---their natural enemy! Now everything is plain sailing in 14 life.It's your opponents(对手)that you are improving indeed,so 15 must go to your opponents.It's true! (     )1.  A. have made (     )2.  A. Where (     )3.  A. afraid at (     )4.  A. about (     )5.  A. little (     )6.  A. learned (     )7.  A.  that (     )8.  A. understood (     )9.  A. fed on (     )10. A. under (     )11. A. another (     )12. A. caught (     )13. A. why (     )14. A. your (     )15. A. cries B. have drawn B. What B. angry with B. out B. a few B. noticed B. ones B. wondered B. offered B. for B. other B. eaten B. where B. our B. greetings C. have got C. Why C. pleased with C. over C. few C. found C. those C. solved C. provided C. at C. the other C. taken C. because C. my C. laughter D. have lost D. How D. grateful to D. of D. a lot D. worked on D. these D. known D. grew up D. with D. others D. kept D. wherever D. their D. thanks