题目内容
Color is very important to most animals for it helps them to get along in the world. Color (21) to make an animal difficult for its enemies to (22) . Many animals match their (23) so well that as long as they do not move no one is (24) to see them. You probably have often "jumped" a rabbit. If you (25) , you know how the rab- bit sits perfectly still (26) you are just a few feet away. You (27) see the rabbit till it runs for its (28) matches very closely the place where it is (29) . Many times you may have walked past a rabbit (30) didn’t run and you never knew it was there at all.One of the most usual color schemes that helps animals to keep (31) being seen, is a dark back and light underpants. If an animal is the same color all (32) , there is always a dark shadow along the animal’s belly (腹部). (33) an enemy couldn’t see the animal he could see this dark shadow. The shadow makes the animal (34) out to view. But if the belly is (35) than the rest of the animal, the shadow will not be noticed. 22（）
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The word science is heard so often, in modem times that almost everybody has some notion of its meaning. On the other hand, its definition is difficult for many people. The meaning of the term is confused, but everyone should understand its meaning and objectives. Just to make the explanation as simple as possible, suppose science is defined as classified knowledge(facts).Even in the true sciences distinguishing fact from fiction is not always easy. For this mason great care should be taken to distinguish between beliefs and truths. There is no danger as long as a clear difference is made between temporary and proved explanations. For example, hypotheses and theories are attempts to explain natural phenomena. From these positions the scientist continues to experiment and observe until they are proved or discredited. The exact statue of any explanation should be clearly labeled to avoid confusion.The objectives of science are primarily the discovery and the subsequent understanding of the unknown. Man cannot be satisfied with recognizing that secrets exist in nature or that questions are unanswerable; he must solve them. Toward that end specialists in the field of biology and related fields of interest are directing much of their time and energy.Actually, two basic approaches lead to the discovery of new information. One, aimed at satisfying curiosity, is referred to as pure science. The other is aimed at using knowledge for specific purposes—— for instance, improving health, raising standards of living, or creating new consumer products. In this case knowledge is put to economic use. Such an approach is referred to as applied science.Sometimes practical-minded people miss the point of pure science in thinking only of its immediate application for economic rewards. Chemists responsible for many of the discoveries could hardly have anticipated that their findings would one-day result in application of such a practical nature as those directly related to life and death. The discoveries of one bit of information opens the door to the discovery of another. Some discoveries seem so simple that one is amazed they were not made years ago, however, one should remember that the construction of the microscope had to precede the discovery of the cell. The host of scientists dedicating their lives to pure science are not apologetic about ignoring the practical side of their discoveries; they know from experience that most knowledge is eventually applied. Pure science, leading to the construction of a microscope, （）
Twins often show great ______, but these twins are an exception.
消除贫困是当代世界的重大课题。发达国家应该从提供资金、减免债务、转让技术、平等贸易等方面，支持和帮助发展中国家振兴经济，提高人民生活水平，这也符合发达国家的长远利益，各国经济共同增长和普遍繁荣，是人类努力的方向。
In 1885 Owen Wister (1850～1938) recorded that "it won’t be a century before the West is simply the true America, with thought, type, and life of its own" and he wanted "to be the hand that once, for all, chronicled and laid bare the virtues and the vices of this extraordinary phase of American social progress." He never became that self-envisioned Tolstoi of the old West, but in 1902 The Virginian was published. It won instant success and skyrocketed its author to fame. It is still the most popular "Western" novel ever published and the master design for the fiction of the Wild West.The Virginian established a literary form, a formula popularly known as "horse opera", whose conventions, cliches, and values have reappeared in novels and short stories, in movies and television serials, ever since. The romantic cowboy is the hero and gentleman, one of those "good men in the humbler walks of life", who sees through shams, defends justice and a lady’s honor, shoots it out with the villain and conquers evil. Because of The Virginian, Wister created a character who is the original type for the Western folk hero. He represents the embodiment of certain American ideals--a man who is equal to all occasions, who shows independence of action, a man who keeps his word who is "a broad-guage fellow living among narrow-guage folk". But the literary device and cowboy code which Wister established dictated that the hero must kill the bad man. This necessity for sanctioning murder and romanticizing of the cowboy as a gentleman prohibited The Virginian and the genre it created from becoming serious fiction, or even an authentic product of the western experience. Instead of achieving his ambition, therefore, Wister gave us a sort of American folk epic, the cowboy story. Owen Wister believed （）
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