单选题In early 2004 eight tiny sensors were dropped from a plane near a military base in California. After hitting the ground, the sensors—also known as smart dust sensors—organized themselves into a network and quickly detected a fleet of military vehicles on the ground. They determined the direction, speed and size of a series of military vehicles traveling along the road and later transmitted the data to a computer at a nearby base camp. Smart dust sens6rs are minicomputers—as small as a grain of rice in some cases—that can monitor and evaluate their physical environment and can relay the information via wireless communication. They can monitor elements such as temperature, moisture, humidity, pressure, energy use, vibration, light, motion, radiation, gas, and chemicals. These devices will soon have many applications, such as use in emergency rescue. Software has been developed to run these minicomputers. A key feature of the software is the ability of the sensors to automatically organize themselves into a communications network and talk to each other via wireless radio signals. If any one connection is interrupted, the sensors will self-correct and pass the information on to the next available sensor. Each sensor has a chip that does the computing work—recording things like temperature and motion at its location. Each sensor also has a tiny radio transmitter that allows it to talk to other sensors within 100 feet or so. With a single network of 10,000 sensors—thought to be the biggest array (排列) of sensors currently possible—you could cover 9 square miles and get information about each point along the way. The data finally works its way to a base station that can send the information to a computer or to a wireless network. The scientists who are working with this technology say smart dust sensors can be used to detect the location or movement of enemy troops in areas too dangerous or remote for soldiers to operate. Scattering hundreds of self-networking sensors from a manned or unmanned plane onto the battlefield, in theory, could produce critical information and lead to strategic advantage. Sensors could also be used to detect the presence of chemical weapons and could give troops the time needed to put on protective gear.

单选题It is implied in Paragraph 3 that graduates should ______.

单选题Honesty is the best policy, as the English saying goes. Unfortunately, honesty often deserts us when no one is watching, British psychologists reported last week. Researchers at UK's Newcastle University set up an experiment in their psychology department's coffee room. They set a kettle, with tea, coffee and milk on the counter and hung up a sign listing the prices for drinks. People helping themselves to a cup of drink were supposed to put a few cents in the box nearby. The scientists hung a poster above the money box, and it changed each week between images of gazing eyes and pictures of flowers. The researchers found that staff paid 2.76 times more for their drinks when the image of the eyes was hung. "Frankly we were shocked by the size of the effect," said Gilbert Roberts, one of the researchers. Eyes are known to be a powerful perceptual (感官的) signal for humans. "Even though the eyes were not real, they still seemed to make people behave more honestly," said Melissa Bateson, a behavioral biologist and leader of the study. Researchers believe the effect sheds light on our evolutionary past. It may arise from behavioral features that developed when early humans formed social groups to strengthen their chances of survival For social groups to work, individuals had to co-operate, rather than act selfishly. "There's an argument that if nobody is watching us, it is in our interests to behave selfishly. But when we're being watched we should behave better. So people see us as co-operative and behave the same way towards us," Bateson said. The new finding indicates that people have a striking response to eyes. That might be because eyes and faces send a strong biological signal we have evolved to respond to. The finding could be put to practical use, too. For example, images of eyes could increase ticket sales on public transport and improve supervision systems to prevent antisocial behavior.

单选题He is ______ taller than me.

单选题{{B}}Passage Three{{/B}} From the beginning, migration has been 6ne of the most conspicuous features of human history. Humanity did not appear simultaneously all over the earth but, according to the current scientific consensus, first evolved in Africa, and from there spread far and wide. Even after mankind had populated most of the planet, migration continued to play a decisive role in history down the centuries, as people contended for territory and the resources that go with it. In many of history's biggest movements of people, the migrants were not volunteers. In the 17th and 18th centuries, 15 million people were taken as slaves from Africa and shipped to Brazil, the Caribbean and North America. In the 19th century, between 10 and 40 million indentured workers (契约工人，苦力) were sent in vast numbers around the world, mainly from China and India. The 20th century's wars in Europe and Asia displaced millions more. But perhaps the most intense episode of migration-under-duress (强迫) in modern times occurred after the partition of India in 1947, when 7 million Muslims fled India for the new state of Pakistan and 7 million Hindus fled in the opposite direction. As individuals, not merely as members of races or religions in flight, people have always traveled in search of a better life. Between the middle of the 19th century and the start of the second world war, 60 million people left Europe and move overseas to the United States, Canada, Latin America, Australia, New Zealand and South Africa. Much of this movement was guided by economic calculation. Most modern migration is of this kind, though nowadays the pull is high wages rather than cheap land. For the 19th century or so, the pattern of migration has shifted a good deal, with changes in government policy playing a key role. Until t914 governments imposed almost no controls. This allowed the enormous 19th-century movement of migrants from Europe to North America. Between 1914 and 1945; partly reflecting security concerns, migration was curtailed. Many countries excluded immigrants. America's Congress passed laws aiming to preserve the country's racial and religious makeup. After 1945 came another great change. Many European countries faced labor shortages. Governments actively recruited immigrants for jobs in their expanding industries. Migration surged again, now not mainly from Europe to North America but from the developing countries to the rich ones. The next big change came in the 1970s. The rich countries were no longer growing quickly and struggling with labor shortages. Recession came to Europe and America, and immigration rules were tightened again. This more restrictive regime continues to apply.

单选题In the world of climate change, it is in the Earth's cold regions where trends can most easily be seen. The cryosphere, where water is found in solid form, is among the most sensitive regions to temperature change. The sensitivity of ice and snow to temperature changes is an early indicator of even relatively small differences, says University of Colorado at Boulder senior researcher Richard Armstrong. He has found that today's receding and thinning sea ice, mountain glacier mass losses, decreasing snow extent, melting permafrost (永久冻土), and rising sea level are all consistent with warming. Global mean temperatures have risen one degree Fahrenheit over the past 100 years. with more than half of the increase occurring in the last 25 years, observes Armstrong who is affiliated with the National Snow and Ice Data Center headquartered at CU-Boulder. "As slight as that may seem, it's enough to make a difference, " said Armstrong. "Now, long-term monitoring of a series of cold region, or cryospheric, parameters (参数) shows that for several decades the amounts of snow and ice around the world have been decreasing. " The extent of Arctic sea ice is shrinking by about 3 percent per decade. but the trends are not uniform. While recent studies have indicated that the ice thickness also had decreased over several decades, new information shows that the ice may have thinned rapidly, Armstrong said. Examination of springtime ice thickness in the Arctic Ocean indicates that the mean ice thickness decreased 1.5 meters (4.8 feet) between the mid-1980s and early 1990s. To mark its 25th anniversary, the National Snow and Ice Data Center has organized a special session at the 2001 Fall Meeting of American Geophysical Union, taking place this week in San Francisco, that illuminates overall changes in the cryosphere. The session begins Tuesday and extends through Thursday afternoon, with 75 contributions from all areas of cryospheric study. Papers and posters include examinations of lake and river ice, glacier dynamics, and mass ice balance studies in polar and continental glaciers, regional and polar snow cover trends, and variations in Canadian ice cap elevations.

单选题Woman: I"m clueless and, quite frankly, I"m getting worried about the future. Man: We"re all in the same boat. Leaving school is a big step. Question: What"s the issue they are facing now?

单选题The idea of building "New Towns" to absorb growth is frequently considered a cure-all for urban problems. It is wrongly assumed that if new residents can be diverted from existing centers. the present urban situation at least will get no worse. It is further and equally wrongly assumed that since European New Towns have been financially and socially successful, we can expect the same sorts of results in the United States. Present planning, thinking, and legislation will not produce the kinds of New Town that have been successful abroad. It will multiply suburbs or encourage developments in areas where land is cheap and construction profitable rather than where New Towns are genuinely needed. Such ill-considered projects not only will fail to relieve pressures on existing cities but will, in fact, tend to weaken those cities further by drawing away high-income citizens and increasing the concentration of low-income groups that are unable to provide tax income. The remaining taxpayers, accordingly, will face increasing burdens, and industry and commerce will seek escape. Unfortunately, this mechanism is already at work in some metropolitan areas. The promoters of New Towns so far in the United States have been developers, builders, and financial institutions. The main interest of these promoters is economic gain. Furthermore, federal regulations designed to promote the New Town idea do not consider social needs as the European New Town plans do. In fact, our regulations specify virtually all the ingredients of the typical suburban community, with a bit of political rhetoric (修辞) thrown in. A workable American New Town formula should be established as firmly here as the national formula was in Britain. All possible social and governmental innovations as well as financial factors should be thoroughly considered and accommodated (容纳) in this policy. Its objectives should be clearly stated, and both incentives and penalties should be provided to ensure that the objectives are pursued. If such a policy is developed, then the New Town approach can play an important role in alleviating America's urban problems.

单选题A: ______.B: No. I'm really not in the mood. A. I've heard that this Chinese restaurant is very good. B. Why don't we go dancing? C. It's Thanksgiving Day. D. It'll do you good to stay home.

单选题Good morning, class. ______ of you wants to do the presentation first? A. Which B. Whom C. What D. Who

单选题"Michael left for California this morning." "Oh, I thought he ______ until next week. " A. hadn't been going B. isn't going C. won't be going D. wasn't going

单选题______ he realized it was already too late for us to return home. A. No sooner it grew dark when B. Hardly it grew dark than C. It was not until dark that D. Scarcely it grew dark than

单选题Operation research is a scientific method of providing executive department with a quantitative basis for decisions ______ the operations under their control. A. regarding B. as to C. on D. considering

单选题You ______ a mosquito here, because the temperature is far below freezing and any mosquito here has been frozen to death. A. can't have seen B. must not have seen C. shall not have seen D. need not have seen

单选题I had no sooner closed the door ______ somebody started knocking on it. A. as B. before C. than D. when

单选题Speaker A: Would you please close the window? I feel a bit cold. Speaker B:______

单选题Where the Galapagos Islands lie today, there was once an unbroken expanse of Pacific. Then the sea began to seethe and simmer, the earth"s crust was pierced, and matter gushed forth con-tinuously. Lava and scoriae (loose, cinderlike lava) piled up until one day spewing volcanoes raised peaks above the brawling sea. Many thousands of years passed before life could settle upon the cooled land. Then wind and waves brought the first hardy seed of primitive plants. After these came others, then insects, liz-ards, and birds. The chance that any animal would survive the trip from the South American con-tinent more than six hundred miles away was slight; only a few hardy species came through alive. This is why there are many gaps in the animal life of the islands. Those that did reach the out-of-the-way islands developed over the ages into a number of quite peculiar forms. Because conditions in the Galapagos differed from those in their original homes, the animals had to change or perish. Only in the Galapagos are there seaweed-eating ma-rine lizards, giant tortoises, and flightless cormorants. In fact, most of the species found in the Galapagos Islands are endemics, they exist only in the archipelago.

单选题Speaker A: Chinese or Italian, what would you prefer for dinner? Speaker B: ______, as far as I don"t have to cook.

单选题Speaker A: Can I help you? Speaker B:______

单选题Woman: Did you think it was a good play? Man: What I didn't understand was the very beginning. Question: What does the man mean?