Of all man’s natural enemies, the one that has caused him more trouble than any other must be the common rat. For centuries, man has been  21  to solve the problem of rats. The ancient Egyptians were probably the first people to try to  22  them with poison, and this method is still being used today. This says a great deal about how  23  this method has been. We have set innumerable  24  , from simple wires to  25  machines that drowned the rats in beer! We have tried to inflect them with  26  developed germs. We’ve  27  tried to raise super cats to kill them. However, we are still losing the  28  .
  So why can’t man manage to  29  a mere animal like the rat? The answer is simply that the rat isn’t a mere animal; It is a very special kind of animal. An average rat  30  : wriggle through a hole no  31  than a $1 coin; climb a brick wall as if it were climbing steps; happily leave a building by being flushed down the toilet, and then return the same  32  ; jump from a fifth storey window and run away  33  ; and last but certainly not least ,  34  so rapidly that a single pair could have 15,000 babies in one year!
    35  all these phyical qualities, we also have the 36 that rats are rather good at not getting caught. They seem to have an almost supernatural ability to   37  when food has been poisoned and a suspicious rat will starve  38  it eats poisoned food. They also seem to be able to  39  a trap with no real difficulty.
  One thing looks certain, we had better find a way to  40  these small brown creatures soon, or it may be too late.
  21. A. Trying B. managing C. coming D. failing
  22. A. solve B. drive C. kill D. murder
  23. A. effective B. efficent C. explict D. extreme
  24. A. troops B. tricks C. tyres D. traps
  25. A.commercial B. complictated C. conventional D. contemporary
  26. A. secretly B. especially C. specially D. separately
  27. A. ever B. never C. just D. even
  28. A. competition B. companion C. battle D. challenge
  29. A. Overcome B. hunt C. grasp D. interrupt
  30. A. should B. can C. must D. may
  31. A. larger B. smaller C. less D. more
  32. A. method B. way C. means D. road
  33. A. harmed B. unharmed C. brave D. clumsy
  34. A. adopt B. grow C. multiply D. accelerate
  35. A. In spite of B. Owing to C. In addition to D. At the mercy of
  36. A. phenomenon B. problem C. principle D. privilege
  37. A. touch B. taste C. feel D. sense
  38. A. after B. when C. since D. before
  39. A. realize B. recognize C. ruin D. rewind
  40. A. win B. hit C. strike D. defeat
  答案 21. A 22. C 23. A 24. D 25. B 26. C 27.D 28. C 29. A 30. B
  31. A 32. B 33. B 34. C 35. C 36. B 37. D 38.D 39. B 40. D