单选题If all the viruses on the planet were to disappear, a global catastrophe would, ______.and the natural ecosystems of the earth would collapse in a spectacular crash under burgeoning populations d insects.

单选题The writer's attitude to the prospect of the ocean is ______.

单选题The role of the UN force this time is to ______ the transport of aid to the parts of the country that need it most. A. further B. oversee C. adopt D. prohibit

单选题We ______ admire his courage and self-confidence. A. can but B. cannot only C. cannot but D. can only but

单选题In charge of an army of seven thousand men, he ______ the oriental city for nine months and finally defeated it.

单选题Though I had tried to explain it as clearly as possible, my explanation seemed not to______.

单选题At this time of the year, university admission offices are _____ with inquiries from anxious applicants.

单选题We have a firm belief that he will Uabide by/U his promise if he gives it to anyone.

单选题Juliet is not at work. She is taking a ______until the end of this week.

单选题We had a marvelous holiday. only the last two days were slightly ______ by weather.

单选题4 In the wake of 11 September, Visionics, a leading manufacturer, issued a fact sheet explaining how its technology could enhance airport security. They called it "protecting civilization from the faces of terror". The company's share price skyrocketed, as did the stocks of other face-recognition companies, and airports across the globe began installing the software and running trials. As the results start to come in, however, the gloss (光滑表面) is wearing off. No matter what you might have heard about face-recognition software, Big Brother it ain't. The concern was based largely on an independent assessment of face-recognition sys tems carried out in 2000 in the U. S. by the Department of Defense. These tests found that to catch 90 percent of suspects at an airport, face-recognition software would have to raise a huge number of false alarms. One in three people would end up being dragged out of the line and that's assuming everyone looks straight at the camera and makes no effort to dis guise himself. Results from the recent airport trials would seem to justify that concern. Most face-recognition systems use some kind of geometric technique to translate a pic ture of a face into a set of numbers that capture its characteristics. Once it has identified these boundaries, the software calculates their relative sizes and positions and converts this geometry into what Visionics calls a "faceprint'. Feed the software a series of mug shots (通缉犯), and it'll calculate their faceprints. Then it can monitor live CCTV images for the faces of known suspects. When it finds a match, it raises an alarm. Even if the system does manage to capture a face, the problems aren't over. The trou hie is that a suspect's faceprint taken from live CCTV is unlikely to match the one in the database in every detail. To give themselves the best chance of picking up suspects, opera tors can set the software so that it doesn't have to make an exact match before it raises the alarm. But there's a price to pay: the more potential suspects you pick up, the more false alarms you get. You have to get the balance just right. Despite the disappointing tests, some people insist that face-recognition technology is good enough to put terrorists off. After all the claims and counter-claims, with no one able to discern (洞察) the truth, the industry may soon have to face up to reality.

单选题We found that television and radio ______ far fewer complaints than did the printed media.

单选题In some ways, the United States has made spectacular progress. Fires no longer destroy 18,000 buildings as they did in the Great Chicago Fire of 1871, or kill half a town of 2,400 people, as they did the same night in Peshtigo, Wisconsin. Other than the Beverly Hill Supper Club fire in Kentucky, in 1977, it has been four decades since more than 100 Americans died in a fire. But even with such successes, the United States still has one of the worst fire death rates in the world. Safety experts say the problem is neither money nor technology, but the indifference of a country that just will not take fires seriously enough. American fire departments are some of the world"s fastest and best equipped. They have to be. The United States has twice Japan"s population, and 40 times as many fires. It spends far less on preventing fires than on fighting them. American fire-safety lessons are aimed almost entirely at children, who die in disproportionately large numbers in fires but whom, contrary to popular myth, start very few of them. Experts say the fatal error is an attitude that fires are not really anyone"s fault. That is not so in other countries, where both public education and the law treat fires as either a personal failing or a crime. Japan has many wood houses, of the estimated 48 fires in world history, that burned more than 10,000 buildings, Japan has had 27. Penalties for causing a severe fire by negligence can be as high as life imprisonment. In the United States, most education dollars are spent in elementary schools. But the lessons are aimed at too limited an audience, just 9 percent of all fire deaths are caused by children playing with matches. The United States continues to rely more on technology than laws or social pressure. There are smoke detectors in 85 percent of all homes. Some local building codes now require home sprinklers. New heaters and irons shut themselves off if they are tipped.

单选题Brazil has become one of the developing world' s great successes at reducing population growth but more by accident than design. While countries such as India have made joint efforts to 61 birth rates, Brazil has had better result without really trying, says George Martine at Harvard. Brazil' s population growth 62 has dropped from 2.99% a year between 1951 and 1960 63 1.93% a year between 1981 and 1990, and Brazilian women now have only 2.7 children on average. Martine says this 64 may have fallen still further since 1990, an achievement that makes it the envy of many other Third World countries. Martine puts it down to, among other things, soap operas (通俗电视连续剧)and installment (分期付款) plans introduced in the 1970s. Both played an important, although indirect, 65 in lowering the birth rate. Brazil is one of the world's biggest producers of soap operas. Globo, Brazil' s most popular television network, shows three hours of soaps six nights a week, while three others show at least one hour a night. Most soaps are based 66 wealthy characters living the high life in big cities. "Although they have never really tried to work in a message towards the problems of reproduction, they describe middle and upper class values--not many children, different attitudes towards sex, women working," says Martine "They sent this image to all parts of Brazil and 67 people conscious of other patterns of behavior and other 68 , which were put into a very attractive pack- age. "Meanwhile, the installment plans tried to 69 the poor to become consumers. "This led to an enormous change in consumption patterns and 70 was incompatible'(不相容的)with un- limited reproduction," says Martine.

单选题You can't let your eyes glide across the lines of a book and ______ an understanding of what you have read. A. come up to B. come across C. come around D. come up with

单选题Last Sunday she came to visit us out of the blue . The italicized phrase means ______.

单选题The Texas Opera Theater was established as a subsidiary of the Houston Grand Opera in order to give young singers performing experience.

单选题For years the girl had harbored her ______ against her stepmother. Today, she finally got the courage to speak it out. A. resentment B. rivalry C. compulsion D. concession