单选题With a wave of his hand, the magician made the duck ______ A. scatter B. vanish C. abandon D. fly away

单选题If they think they are going to win over us by obstinately______and refusing to make the slightest concession, they are mistaken. A. holding out B. holding to C. holding over D. holding up

单选题John Smith is a______ ; he helps to write newspapers.

单选题One day in 1963, a dolphin named Elvar and a famous astronomer, Carl Sagan, were playing a little game. The astronomer was visiting an institute which was looking into the way dolphins communicate with each other. He was standing at the edge of one of the tanks where several of these highly intelligent, friendly creatures were kept. Elvar had just swum up alongside him and had turned on his back. He wanted Sagan to scratch his stomach again, as the astronomer had done twice before. But this time Elvar was too deep in the water for Sagan to reach him Elvar looked up at Sagan, waiting. Then, after a minute or so, the dolphin leapt up through the water into the air and made a sound just like the word "More!" The astonished astronomer went to the director of the institute and told him about the incident. "Oh, yes. That's one of the words he knows," the director said, showing no surprise at all. Dolphins have bigger brains in proportion to their body size than humans have, and it has been known for a long time that they can make a number of sounds. What is more, these sounds seem to have different functions, such as warning each other of danger. Sound travels much faster and much further in water than it does in air. That is why the parts of the brain that deal with sound are much better developed in dolphins than in humans. But can it be said that dolphins have a "language" in the real sense of the word? Scientists don't agree on this. A language is not just a collection of sounds, or even words. A language has a structure, or what we call a grammar. The grammar of a language helps to give it meaning. For example, the two questions "Who loves Mary?" and "Who does Mary love?" mean different things. If you stop to think about it, you will see that this difference doesn't come from the words in the question but from the difference in structure. That is why the question "Can dolphins speak?" can't be answered until we find out if dolphins not only make sounds but also arrange them in ways which affect their meaning.

单选题Building this road will ______ the construction of ten bridges, then the total cost reaches 1 million US Dollars. A. evolve B. involve C. revolve D. devolve

单选题It comes as no surprise that societies have codes of behavior. The character of the codes, on the other hand, can often be ______.

单选题Roger gave me some beautiful Japanese stamps in______ for two sets of 1960 British special issue.

单选题Most people______ driving on icy roads, but he rather enjoys it.

单选题Part of the lake has been polluted. You can see the water is covered with ______ oil.

单选题Even the most arbitrary and______ corporation today must be aware of the attitudes of its employees; management may at times be more or less______, but all must respect the power of an organized work force.

单选题The author believes that in the era of the Information Technology boom the distance between people' s hearts has become the farthest distance on earth because ______.

单选题There have been several attempts to introduce gayer colors and styles in men's clothing, but none of them ______.

单选题For us it is a big and dark secret;to______it would be to jeopardize our future, confessed an avi-aphobe who is currently undergoing therapy.

单选题Fossils of A(plant) that have B(been extinct) for C(fifty million years) have been found in large deposits of amber D(near) the Baltic Sea.

单选题The word "foolish" is too mild to describe your behavior. I would prefer the word ______.

单选题He studied at a famous college when he was young, ______contributed to his success in later life.

单选题The destruction of the Twin Towers in New York City ______ shock and anger throughout the world.

单选题The losing candidate immediately after the polls had closed. A. confessed B. conceded C. concurred D. admitted

单选题3 The word science is heard so often in modern 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 objec tives. Just to make the explanation as simple as possible, suppose science is defined as clas- sified knowledge (facts). Even in the true sciences distinguishing fact from fiction is not always easy. For this reason 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 explana tions. For example, hypotheses and theories are attempts to explain natural phenome na. From these positions the scientist continues to experiment and observe until they are proved or discredited. The exact status 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 knowl edge 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 ap proach 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 dis coveries 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 sim ple 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 sci entists 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 ap plied.