单选题Are we at the beginning of another Age of Exploration? Perhaps even more important, are we at the beginning of 1 Age of Colonization? As the population of the world increases towards the point 2 the earth can no longer support all the people 3 on it, the second question becomes urgent. Will we discover a new world, 4 Columbus did, on which human life will be possible? At this point in the space age, no one can really answer these questions. We can say, 5 that we will not see tomorrow the kind of space travel that 6 fiction and the movies have shown. It will be a long time before we have flight that run 7 to human colonies on the moon or on, one of the planets. We are not even going to be able to 8 immediate advantages of the minerals that we may find on the planets 9 our own solar system. Great problems must be solved 10 we could send colonists out into place. The distances that must be 11 and the length of time it takes to do that can hardly be 12 . There are also dangers that we still do not realty understand, from radiation, for example, or from pieces of matter 13 in space, or from contamination forms of life that might 14 there. There is also need for humans to take their own environment into space 15 them. So far no "island" has been discovered in space on which people can exist without systems that 16 life, and these systems must accompany any future space 17 Finally, on the most practical 18 there has to be enormous expense 19 in space exploration. The U.S. and Russian governments have already spent billions of dollars for projects 20 which they can receive a return only in knowledge and not in money.

单选题The ______ goal of the book is to help bridge the gap between research and teaching, particularly between researchers and teachers.

单选题It can be inferred from the article that the majority of tropical forests ______.

单选题 {{B}}Questions 27—30 are based on a report about generation gap. You now have 20 seconds to read Questions 27—30.{{/B}}

单选题The three points of view that indicate the relations of individuals are ______.

单选题The company has consistently denied responsibility, but it agreed to the settlement to avoid the expense of______.

单选题Some people believe that "King John" was written by Shakespeare, but some people it might be written by an ______ author.

单选题Costs for regulation of business actually are a hidden tax severely reducing the competitive ness of domestic businesses ______ when they face an increasingly global marketplace.

单选题There are probably very few cases in which different races have lived in Ucomplete/U in a single country for long periods.

单选题To impress a future employer, one should dress neatly and be ______.

单选题Her shabby clothes were often made ______ by her classmates.

单选题Which of the following is true according to the last paragraph?

单选题A ship is in great danger. Please point out the ship's exact ______ .

单选题Which one of the following statements is NOT true according to the article?

单选题Throughout the empire of Kublai Khan, money made of paper was used for business, ______,something unheard of in Europe.

单选题Fun is what we experience during an act. Happiness is what we experience after an act. It is a deeper, more ______ emotion.

单选题One year ago we stared aghast at images of the Southeast Asian tsunami. Video cameras taken on vacation to record the everyday pleasures of the beach were suddenly turned to quivering utility as they documented the panic and mayhem of a natural disaster. Who can forget the disbelief in the recorded voices? This can't be happening to us. Human beings are never prepared for natural disasters. There is a kind of optimism built into our species that seems to prefer to live in the comfortable present rather than confront the possibility of destruction, It may happen, we seem to believe, but not now, and not to us. Mount Vesuvius has been erupting since historical records began. The eruption of A. D. 79 both destroyed Pompeii and preserved it for posterity. Pliny the Younger starkly recorded the details in prose that can still be read as a scientific ac-count. Yet houses are still being erected today at vulnerable sites around Vesuvius, in the face of the geological inevitability of further eruptions. Disasters are described as "acts of God". Whenever a natural catastrophe occurs, old questions resurface. How can we reconcile tragedy with the idea of a beneficent God? And with that question, the notion of punishment is never far behind. If classical religions were wont to attribute disasters to the wrath of the gods, even in this scientific age the old explanations still have their attractions. And who might not sneakily still wish to believe that a saint could intercede on our behalf? But there is another kind of disaster. Many scientists think that the Gulf Coast hurricanes may be a symptom of climate change. Carbon emissions have been accelerating more rapidly within a generation or two: this is not the result of some creeping plate indifferent to the fate of humans; this is our responsibility. However, there is still the same, almost willful blindness to the dangers of climate change; after all, the sun still rises, the crops still ripen--why worry? Geology tells us that there have been "green-house worlds" in the distant past. These have been times when seas flooded over continents. Even modest sea-level rises would spell the end of densely populated areas of the world like Bangladesh. In such a case, invoking the God to look after us for the best is just pie in the sky. These are not "acts of God" but acts of man. We should be ashamed of the consequences of our own willing blindness.

单选题Clark felt that his ______ in one of the most dramatic medical experiments of all time was worth the suffering he underwent. A. presentation B. participation C. apprehension D. appreciation

单选题It was ______ of them to share their meal with their out-of-work neighbors.

单选题The doctor hit me just below the knee to test my ______ .