Of a11 the characteristics that man has used to distinguish himself from“lower”animals，the desire to explore the unknown may be the most enduring.As the Norwegian polar explorer and oceanographer Fridtjof Nansen observed，“Man wants to know，and when he ceases to do so，he is no longer man.”

　　The annual migrations of wildfowl and many other animals certainly cannot be regarded as a form of exploration，because such movements are actually only shifts from one habitat to another for the purpose of avoiding seasonal climatic variations.4) Likewise，the gradual expansion by certain animals into new ranges is not exploratory but rather merely a shift to a 1ess crowded or more favourable environmental setting.To be sure，mankind also has been involved in movements of this sort when subjected to population and other pressures.Then，too，economic and military considerations have frequently been major driving factors in human expansion into new realms.5)Nonetheless，in numerous instances，man‘s attempts at exploration have been marked by imaginative leaps across hostile stretches，sometimes at great risks， to reach something undefined simply for its own sake.

　　Much of the history of exploration—certainly of modern geographical exploration—has been European.6) Such has been the case not because Europeans possessed superior curiosity or some other internal force but because whatever events channeled their societies toward an advanced level of technology allowed them to expend more energy on exploration.The rapid growth and consolidation of their kingdoms provided them with an opportunity to exploit new discoveries fully.By contrast，the great Asian kingdoms，though no less capable，turned inward and erected walls between themselves and the“barbarians”of the outside world.

　　The 20th century has witnessed the last stages of exploration of the Earth‘s surface and the initial attempts to explore the deep sea and space.Scientific attention today is primarily directed toward these new frontiers.In addition to this emphasis on undersea and space exploration，efforts are also being made to investigate the interior of the Earth，knowledge of which still remains relatively limited.

　　1. What Nansen said means that____.

　　[A]a man never stops exploring the unknown until he dies

　　[B]exploration of the unknown is a characteristic of man

　　[C]ignorant people are no more than “lower” animals

　　[D]a man is not a brave man unless he shows curiosity about the unknown

　　2. According to the author，true exploration is marked by____.

　　[A]migrating from a familiar area to a new one

　　[B]moving into a less crowded and favourable environmental setting

　　[C]venturing into an unknown，sometimes risky，world

　　[D]gradually expanding into new ranges

　　3. The Europeans were often the pioneers in exploration because____.

　　[A]they had daring spirits and were more curious about the unknown

　　[B]social development offered them the means to explore the world

　　[C]they had more internal driving forces to urge them in such attempts

　　[D]they were more capable of such activities than the Asians

　　4. In the last sentence of Paragraph 3，the word“barbarians”probably refers to____.

　　[A]the fiercest enemies

　　[B]savage and uncivilized people

　　[C]hostile neighboring countries

　　[D]ambitious Europeans powers

　　5. The 20th century explorers are similar to the earlier explorers in their curiosity about____.

　　[A]the deep sea [B]the space

　　[C]the interior of the Earth [D]the surface of the Earth

　　1. [B] 意为：对未知领域进行探索是人类的特性。在第一段，Nansen所说的意思是：人类总是想去认识事物，如果他们失去这种欲望，他们就无所谓人了。

　　2. [C] 意为：敢于冒险进人未知的——有时是危险的区域。参阅第二段最后一句，本句中stretches应理解为“区域(或地段)”，undefined应根据上下文理解为“未知的”。本段否定了几种做法，认为这些做法都称不上是探险;在作者看来，只有最后一句提到的情况才算得上是探险活动。

　　3. [B] 根据第三段第二句，探险者多为欧洲人，这并不是因为他们好奇心强或内在的动力大，而是因为历史将他们的社会推向了更高的技术水平，这使得他们可以花更多的精力来从事冒险活动。

　　4. [B] 意为：野蛮而未开化的人。该词意为“野蛮人”，是文明社会对未开化民族带有偏见的称呼。

　　5. [D] 第四段第一句提到，20世纪进入探索地球表面的最后阶段，而开始了对深海区域和太空的探索。由此可以看出，对地球表面的探索在20世纪还在继续。