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Usually, there are two reasons to pursue scientific knowledge: forthe sake of the knowledge itself, and for the practical use of that knowledge.Because this second aspect of science effects the lives of most people, 31 it is much more familiar than the first. Knowledge must be gained,however, after it can be applied, and often the most important technological 32 advances arise from research pursued for its own sake.Traditionally, new technology has concerned with the construction 33 of machines, structures, and tools in a relatively large scale. The 34 development of materials for building bridges, skyscrapers or highwaysis an example of this, as it is the development of the internal-combustion 35 engine and the nuclear reactor. While such activities involve all sectionsof the sciences, the overriding goal has been the same, that is, improve 36 the human condition by finding good ways to deal with the macroscopic world. 37 Since World War Ⅱ, the focus of technological activity underwenta major change. While the old activities are still pursued, they have beenlargely superseded by applications of technology at the microscopic level.Instead of building large-scale structures and machines, modern-daytechnology tends to concentrate on finding improving ways to transfer 38 information and to develop new materials by studying the way atoms cometogether. The silicon chip and microelectronics typify this new technologicaltrend, as did the blossoming of genetic engineering. The trend can be 39 expected to continue for the foreseeable decades. 40
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As anxiety-makers, examinations are second to none. That isbecause so much depends on it. They are the mark of success 21 or failure in our society. One"s whole future may be decided onone fateful day. It doesn"t matter that he wasn"t feeling verywell, or that his mother died. Things like that don"tcount on: the exam goes on. No one can give of his best when 22 he is in mortal terror, or after a sleepless night, yet this is preciselywhat the examination system expects you to do. The moment 23 a child begins school, he enters into a world of vicious competition 24 where success and failure are clearly defined and measured.Can we wonder at the increasing number of "drop-outs": young peoplewho are written off as utter failures before they have even embarked 25 a career Can we be surprised at the suicide rate among studentsA good education should, among other things, train one tothink for himself. The examination system does nothing but that. 26 What has to be learnt is rigidly laid down by a syllabus, so the studentis encouraged to memorize. Examinations do not motivate a studentto read widely, but restrict his reading; they do not enable him to seek 27 more and more knowledge, but induce cramming. They lower thestandards of teaching, for they deprive teachers off all freedoms. 28 Teachers themselves are often judged by examination results andinstead of teaching their subjects, they are reducing to training their 29 students in exam techniques which they despise of. The most 30 successful candidates are not always the best educated; they arethe best trained in the technique of working under duress.
直线l1与直线l2：3x+4y+5=0之间的距离是1． (1)直线l1的方程为3x+4y=-10． (2)直线l1的方程为3x-4y=0．
When Christopher Columbus landed in the New World,the North American continent was area of astonishing ethnic 11 and cultural diversity. North of the Rio Grande, which nowmarks the border among the United States and Mexico, was a 12 population of over 12 million people representing approximately400 distinct cultures, 500 languages, and a remarkablevariety of political and religious institutions and physical andethic types. Compared to the Europeans, the Indian peoples 13 were extraordinary heterogeneous, and they often viewedthe Europe as just another tribe. 14 These varied tribal cultures were as diversified as theLand the Indians lived. In the high plains of the 15 Dakotas, the Mandan developed a peaceful communalSociety centered around agriculture. Only a few hundred milesoff, however, in the northwestern Montana, the Black feet 16 turned from agriculture and began to use horse, which had beenintroduced by the Spaniards. As skilled riders they became 17 hunters and fighters and developed a fierce and aggressiveculture centered around the buffalo. In the eastern woodlandssurrounding the Great Lakes, the Potawatomis were expertfisherman, canoe builders, and hunters. In the Northeast thesix Iroquois nations were among the most political 18 sophisticated people in the world, formed the famed Iroquois 19 confederation, that included the Senecas and the Mohawks. 20 This confederation, with its systems of checks and balances,provided a model for the United States constitutions.
Until the very latest moment of his existence, man has been bound to theplanet on which he originated and developed. Now he has the capability to 1 leave that planet and move out into the universe to those worlds which he hasknown previously: only directly. Men have explored parts of the moon, put space- 2 ships in orbit around another planet and possibly within the decade will land into 3 another planet and explore it.Can we be too bold as to suggest that we may be able to colonize other 4 planet within the not-too-distant future Some have advocated such a procedure as 5 a solution to the population problem: ship the excess people off to the moon. Butwe must keep in head the billions of dollars we might spend in carrying out the 6 project. To maintain the earth"s population at its present level, we would haveto blast off into space 7500 people every hour of every day of the year.Why are we spending so little money on space exploration 7 Consider the great need for improving many aspects of the global environment, one 8 is surely justified in his concern for the money and resources that they are poured 9 into the space exploration efforts. But perhaps we should look at both sides ofthe coin before arriving hasty conclusions. 10
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