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问题 解答题

长期大量使用抗生素，可能使病菌产生较强的抗药性．______．

答案

在抗生素刚被使用的时候，能够杀死大多数类型的病菌．但少数病菌由于变异而具有抵抗抗生素的特性，不能被抗生素杀死而生存下来，并将这些变异遗传给下一代．因此，下一代就有更多的具有抗药性的个体，经过抗生素的长期选择，就形成了抗药性较强的病菌．故此题说法正确．

故答案为：√．

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We might marvel at the process made in every field of study, but the method of testing a person’s knowledge and ability remain as primitive as ever they were. It really is extraordinary that after all these years educationists have still failed to devise anything more efficient and reliable than examinations.
41. ______
They may be a good means of testing memory, or the knack of working rapidly under extreme pressure, but they can tell you nothing about a person’s true ability and aptitude.
42. ______
Your whole future may be decided in one fateful day. It doesn’t matter that you weren’t feeling very well, or that your mother died. Little things like that don’t count: the exam goes on. no one can give of his best when he is in mortal terror, or after a sleepless night, yet this is precisely what the examination system expects him to do. The moment a child begins school, he enters a world of vicious competition where success and failure are clearly defined and measured. Can we wonder at the increasing number of "dropouts": young people who are written off as utter failures before they have even embarked on a career Can we be surprised at the suicide rate among students
43. ______
Examinations do not motivate a student to read widely, but to restrict his reading; they do not enable him to seek more and more knowledge, but induce cramming. They lower the standards of teaching, for they deprive the teacher of all freedom. Teachers themselves are often judged by examination results and instead of teaching their subjects, they are reduced to training their students in exam techniques which they despise. The most successful candidates are not always the best educated; they are best trained in the technique of working under duress.
44. ______
Examiners are only human. They get tried and hungry; they make mistakes. Yet they have to mark stacks of hastily scrawled scripts in a limited amount of time. They work under the same sort of pressure as the candidates. And their word carries weight. After a judge’s decision you have the right of appeal, but not after an examiner’s.
45. ______
Is it cynical to suggest that examinations are merely a profitable business for the institutions that run them This is what it boils down to in the last analysis. The best comment on the system is this illiterate message recently scrawled on a wall: "I were a teenage drop-out and now I am a teenage millionaire."
[A] A good education should, among other things, train you to think for yourself. The examination system does anything but that. What has to be learnt is rigidly laid down by a syllabus, so the students are encouraged to memorize.
[B] The results on which so much depends are often nothing more than a subjective assessment by some anonymous examiner.
[C] Examinations can be taken as a test of a student’s knowledge about a particular subject which would tell the student where he stands among others, and how much he knows and how much he ought to know.
[D] As anxiety-makers examinations are second to none. That is because so much depends on them. They are the mark of success or failure in our society.
[E] The student appearing for the exam takes it under extreme tension and pressure because he knows that he has only one chance to prove his worth and if he fails, he will be left behind for the rest of his life.
[F] For all the pious claim that examinations test what you know, it is common knowledge that they more often do the exact opposite.
[G] There must surely be many simpler and more effective ways of assessing a person’s true abilities.
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