Most young people enjoy some form. of physical activity. It may be walking, bicycling, or swimming, or in winter, skating or skiing. It may be a game of some (11) -football, hockey, golf or tennis. It may be mountaineering. Those who have a passion for climbing high and difficult mountains are often (12) with astonishment. Why are men and women willing to suffer cold and hardship, and to take risks on high mountains? This astonishment is caused, (13) , by the difference between mountaineering and other forms of activity to which men give their leisure.

Mountaineering is a sport and (14) a game. There are no man-made rules, as there are for such games as golf and football. There, (15) , rules of a different kind which it would be dangerous to ignore, but it is this freedom from man-made rules that makes mountaineering (16) to many people. Those who climb mountains are free to use their own methods.

If we compare mountaineering and other more (17) sports, we might think that one big difference is that mountaineering is not a “team game”. We should be mistaken (18) this. There are, it is true, no “matches” between “team” of climbers, but when climbers are on a rock face linked by a rope on which their lives may depend, there is (19) teamwork.

The mountain climber knows that he may have to fight forces that are stronger and more powerful than man. He has to fight the forces of (20) . His sport requires high mental and physical qualities.

这些商品的价格从几美元到数百美元不等。

What, then, is a good education at the end of the twentieth century? Some educators suggest that it should include foreign languages and the study of foreign cultures；a mastery of English, including the ability to write and speak well, because communications have become all-important in the modern world. and also because “a person who doesn't speak and write Clearly doesn't reason clearly either” ; some knowledge of the social sciences(sociology, psychology)that deal with human relations and human problems；some basic knowledge of modem information systems, since the educated professionals of tomorrow will have to understand their machines. Is that all? “No, of course not. ”answer the educators, “We have not mentioned the two great building blocks of education：history and literature!”

Is this truly the best modern education? Perhaps. But every educator would add or subtract a few subjects. And no matter what list of courses would be offered, it would not be approved by all. Not only do the professors have their own ideas on the matter, but the students have theirs' too. “I don't believe, ”protested a Harvard student when his university revised its programs, “I don't believe that colleges have the fight to define what an educated person is. ”But then, who has?

电脑能帮助解决生命研究中的许多问题。

研究人员发现你梦中出现的人越多你醒来时就会越快乐。

社会对你玩或不玩是极不关心的。

It is natural for a laborer to imagine that the______(few)hours he has to spend laboring, and the more hours he is free to play, the better.

重要的不是你分配了多少时间去学习, 而是你在学习时学到了多少东西。

If the neutron star is very large(much bigger than our sun)the process of shrinking may be so intense that a black hole______(result).

In 1992, Clinton won in states that gave him an______(overwhelm)370 electoral votes, compared with 168 for Bush and none for Perot.

was supposed to______(pay)￡120 but I never received that amount.