单选题The Science of the Future Until recently, the "science of the future" was supposed to be electronics and artificial intelligence. Today it seems more and more likely that the next great breakthroughs in technology will be brought through a combination of those two sciences with organic chemistry and genetic engineering. This combination is the science of biotechnology. Organic chemistry enables us to produce marvelous synthetic (合成的) materials. However, it is still difficult to manufacture anything that has the capacity of wool to conserve heat and also to absorb moisture. Nothing that we have been able to produce so far comes anywhere near the combination of strength, lightness and flexibility that we find in the bodies of ordinary insects. Nevertheless, scientists in the laboratory have already succeeded in "growing" a material that has many of the characteristics of human skin. The next step may well be "biotech hearts and eyes" which can replace diseased organs in human beings. These will not be rejected by the body, as is the case with organs from humans. The application of biotechnology to energy production seems even more promising. In 1996 the famous science-fiction writer, Arthur C. Clarke, many of whose previous predictions have come true, said that we may soon be able to develop remarkably cheap and renewable sources of energy. Some of these power sources will be biological. Clarke and others have warned us repeatedly that sooner or later we will have to give up our dependence on non-renewable power sources. Coal, oil and gas are indeed convenient. However, using them also means creating dangerously high levels of pollution. It will be impossible to meet the growing demand for energy without increasing that pollution to catastrophic (灾难性的) levels unless we develop power sources that are both cheaper and cleaner. It is attempting to think that biotechnology or some other "science of the future" can solve our problems. Before we surrender to that temptation we should remember nuclear power. Only a few generations ago it seemed to promise limitless, cheap and safe energy. Today those promises lie buried in a concrete grave in a place called Chernobyl, in the Ukraine. Biotechnology is unlikely, however, to break its promises in quite the same or such a dangerous way.

单选题 Racial Prejudice In some countries where racial prejudice is acute, violence has been taken for granted as a means of solving differences; and this is not even questioned. There are countries {{U}} {{U}} 1 {{/U}} {{/U}}the white man imposes his rude by brute (粗暴) force; there are countries where the black man protests by {{U}} {{U}} 2 {{/U}} {{/U}}fire to cities and by looting and pillaging (抢夺). Important people on both sides, who would in other respects appear to be reasonable men, get up and calmly argue in {{U}} {{U}} 3 {{/U}} {{/U}}of violence as if it were a legitimate (合法的) solution, {{U}} {{U}} 4 {{/U}} {{/U}}any other. What is really frightening, what really {{U}} {{U}} 5 {{/U}} {{/U}}you with despair, is the realization that when it comes to the crunch (关键时刻), we have made no actual {{U}} {{U}} 6 {{/U}} {{/U}}at all. We may wear collars and ties instead of war paint, but our instincts remain basically unchanged. The whole of the recorded {{U}} {{U}} 7 {{/U}} {{/U}}of the human race, that tedious documentation of violence, has taught us absolutely nothing. We have still not learnt that {{U}} {{U}} 8 {{/U}} {{/U}}never solves a problem but makes it more acute. The sheer horror, the bloodshed and the suffering {{U}} {{U}} 9 {{/U}} {{/U}}nothing. No solution ever comes to {{U}} {{U}} 10 {{/U}} {{/U}}the morning after when we dismally (阴郁地) contemplate the smoking ruins and wonder what hit us. The truly reasonable men who {{U}} {{U}} 11 {{/U}} {{/U}}where the solutions lie are finding it harder and harder to get a hearing. They are despised, mistrusted and even persecuted {{U}} {{U}} 12 {{/U}} {{/U}}their own kind because they advocate such apparently outrageous things as low enforcement. If half the energy that goes into {{U}} {{U}} 13 {{/U}} {{/U}}acts were put to good use, if our efforts were directed at {{U}} {{U}} 14 {{/U}} {{/U}}up the slums and ghettos (贫民窟), at improving living standards and providing education and employment for all, we would not have gone a long way to {{U}} {{U}} 15 {{/U}} {{/U}}at a solution.

单选题People in the little town lived a life of ease .

单选题When Jack eventually overtook the last truck he pulled over to the inside lane.A. skippedB. passedC. reachedD. led

单选题TV Games Shows One of the most fascinating things about television is the size of the audience. A novel can be on the "best sellers" list with a sale of fewer than 100,000 copies, but a popular TV show might have 70 million TV viewers. TV can make anything or anyone well known overnight. This is the principle behind "quiz" or "game" shows, which put ordinary people On TV to play a game for the prize and money. A quiz show can make anyone a star, and it can give away thousands of dollars just for fun. But all of this money can create problems. For instance, in the 1950s, quiz shows were very popular in the U. S. and almost everyone watched them. Charles Van Doren, an English instructor, became rich and famous after winning money on several shows. He even had a career as a television personality. But one of the losers proved that Charles Van Doren was cheating. It turned out that the show"s producers, who were pulling the strings, gave the answers to the most popular contestants beforehand. Why? Because if the audience didn"t like the person who won the game, they turned the show off. Based on his story, a movie under the title "Quiz Show" is on 40 years later. Charles Van Doren is no longer involved with TV. But game shows are still here, though they aren"t taken as seriously. In fact, some of them try to be as ridiculous as possible. There are shows that send strangers on vacation trips together, or that try to cause newly married couples to fight on TV, or that punish losers by humiliating them. The entertainment now is to see what people will do just to be on TV. People still win money, but the real prize is to be in front of an audience of millions.

单选题It is said the houses aidng this street will soon be {{U}}demolishe{{/U}}

单选题A plastic wheel can be as {{U}}tough{{/U}} as a metal one.

单选题Because of Delaware’s lenient laws regarding business incorporation, many companies have their {{U}}headquarters{{/U}} in the state’s largest city, Wilmington.

单选题I don't quite follow what she is saying A. believe B. understand C. explain D. accept

单选题The Best Way to Reduce Your Weight You hear this: "No Wonder you are fat. All you ever do is eat. " You feel sad: "I skip my breakfast and supper. I run every morning and evening. What else can I do?" Basically you can do nothing. Your genes, not your life habits, determine your weight and your body constantly tries to maintain it. Albert Stunkard of the University of Pennsylvania found from experiments that, "80 percent of the Children of two obese parents become obese, as compared with no more than 14 percent of the offspring of two parents of normal weight. " How can obese people become normal or even thin through dieting? Well, dieting can be effective, but the health costs are tremendous. Jules Hirsch, a research physician at Rockefeller University, did a study of eight fat people. They were given a liquid formula providing 600 calories (卡路里) a day. After more than 10 weeks, the subjects lost 45 kg on average. But after leaving the hospital, they all regained. The results were surprising: by metabolic measurement, fat people who lost large amounts of weight seemed like they were starving. They had psychiatric problems. They dreamed of food or breaking their diet. They were anxious and depressed (沮丧的) ; some were suicidal. They hid food in their rooms. Researchers warn that it is possible that weight reduction doesn't result in normal weight, but in an abnormal state resembling (类似) that of starved non-obese people. Thin people, however, suffer from the opposite: They have to make a great effort to gain weight. Ethan Sims, of the University of Vermont, got prisoners to volunteer to gain weight. In four to six months, they ate as much as they could. They succeeded in increasing their weight by 20 to 25 percent. But months after the study ended, they were back to normal weight and stayed there. This did not mean that people are completely without hope in controlling their weight. It means that those who tend to be fat will have to constantly battle their genetic inheritance if they want to significantly lower their weight. The findings also provide evidence for something scientists thought was true -- each person has a comfortable weight range. The range might be as much as 9 kg. Someone might weigh 60-69 kg without too much effort But going above of below the natural weight range is difficult. The body resists by feeling hungry or full and changing the metabolism to push the weight back to the range it seeks.

单选题All living organisms, {{U}}regardless of{{/U}} their unique identity, have certain biological, chemical, and physical characteristics in common.

单选题His imagination transformed shadows into a monster. A. a beast B. a ghost C. a giant D. an angel

单选题I am sure to tell you that there"s no danger.

单选题Longer Lives for Wild Elephants Most people think of zoos as safe places for animals, where struggles such as difficulty finding food and avoiding predators don"t exist. Without such problems, animals in zoos should live to a ripe old age. But that may not be true for the largest land animals on Earth. Scientists have known that elephants in zoos often suffer from poor health. They develop diseases, joint problems and behavior changes. Sometimes, they even become infertile, or unable to have babies. To learn more about how captivity affects elephants, a team of international scientists compared the life spans of female elephants born in zoos with female elephants living outdoors in their native lands. Zoos keep detailed records of all the animals in their care, documenting factors such as birth dates, illnesses, weight and death. These records made it possible for the researchers to analyze 40 years of data on 800 African and Asian elephants in zoos across Europe. The scientists compared the life spans of the zoo-born elephants with the life spans of thousands of female wild elephants in Africa and Asian elephants that work in logging camps, over approximately the same time period. The team found that female African elephants born in zoos lived an average of 16.9 years. Their wild counterparts who died of natural causes lived an average of 56 years—more than three times as long. Female Asian elephants followed a similar pattern. In zoos, they lived 18.9 years, while those in the logging camps lived 41.7 years. Scientists don"t yet know why wild elephants seem to fare so much better than their zoo-raised counterparts. Georgia Mason, a biologist at the University of Guelph in Canada who led the study, thinks stress and obesity may be to blame. Zoo elephants don"t get the same kind of exercise they would in the wild, and most are very fat. Elephant social lives are also much different in zoos than in the wild, where they live in large herds and family groups. Another finding from the study showed that Asian elephants born in zoos were more likely to die early than Asian elephants captured in the wild and brought to zoos. Mason suggests stress in the mothers in zoos might cause them to have babies that are less likely to survive. The study raises some questions about acquiring more elephants to keep in zoos. While some threatened and endangered species living in zoos reproduce successfully and maintain healthy populations, that doesn"t appear to be the case with elephants. "Currently, zoos are net consumers of elephants, not net producers," Mason says.

单选题Michael is now merely a good friend.

单选题The boys broke into excited cheering.

单选题U.S. to Start $ 3.2 Billion Child Health Study in January A study that will cost $ 3.2 billion and last more than two decades to track the health of 100,000 U. S. children from before birth to age 21 will be launched in January, U. S. health officials said on Friday. Officials from the U. S. government's National Institutes of Health said they hope the study, to be conducted at 105 locations throughout the United States, can help identify early-life influences that affect later development, with the goal of learning new ways to treat or prevent illness. The study will examine hereditary(遗传的) and environmental factors such as exposure to certain chemicals that affect health. Researchers will collect genetic and biological samples from people in the study as well as samples from the homes of the women and their babies including air, water, dust and materials used to construct their residences, the NIH said. Officials said more than $ 200 million has been spent already and the study is projected to cost $3.2 billion. "We anticipat that in the long term(从长远来说), what we learn from the study will result in a significant savings in the nation's health care costs," Dr. Duane Alexander, who heads the NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development, told reporters. The study will begin in January. when the University of North Carolina and the Mount Sinai School of Medicine in New York start signing up(使报名从事) pregnant women whose babies will then be followed to age 21. Some of the early findings will be 'about factors behind pre-term birth(早产), which has become more common in recent years, according to Dr. Peter Scheidt of the NIH, who heads the study. The people taking part will be from rural, urban and suburban areas, from all income and educational levels and from all racial groups, the NIH said.

单选题What were the {{U}}consequences{{/U}} of the decision she had made?

单选题Older Volcanic Eruptions Volcanoes were more destructive in ancient history, not because they were bigger, but because the carbon dioxide they released wiped out life with greater ease. Paul Wignall from the University of Leeds was investigating the link between volcanic eruptions and mass extinctions. Not all volcanic eruptions killed off large numbers of animals, but all the mass extinctions over the past 300 million years coincided with huge formations of volcanic rock. To his surprise, the older the massive volcanic eruptions were, the more damage they seemed to do. He calculated the "killing efficiency" for these volcanoes by comparing the proportion of life they killed off with the volume of lava (熔岩) that they produced. He found that size for size, older eruptions were at least 10 times as effective at wiping out life as their more recent rivals. The Permian (二叠纪) extinction, for example, which happened 250 million years ago, is marked by floods of volcanic rock in Siberia that cover an area roughly the size of western Europe. Those volcanoes are thought to have pumped out about 10 gigatonnes (十亿吨) of carbon as carbon dioxide. The global warming that followed wiped out 80 percent of all marine genera (种类) at the time, and it took 5 million years for the planet to recover. Yet 60 million years ago, there was another huge amount of volcanic activity and global warming but no mass extinction. Some animals did disappear but things returned to normal within ten thousands of years. "The most recent ones hardly have an effect at all," Wignall says. He ignored the extinction which wiped out the dinosaurs 65 million years ago, because many scientists believe it was primarily caused by the impact of an asteroid (小行星). He thinks that older volcanoes had more killing power because more recent life forms were better adapted to dealing with increased levels of CO 2 . Vincent Courtillot, director of the Paris Geophysical Institute in France, says that Wignall"s idea is provocative. But he says it is incredibly hard to do these sorts of calculations. He points out that the killing power of volcanic eruptions depends on how long they lasted. And it is impossible to tell whether the huge blasts lasted for thousands or millions of years. He also adds that it is difficult to estimate how much lava prehistoric volcanoes produced, and that lava volume may not necessarily correspond to carbon dioxide emissions.

单选题After the accident, my back was very painful for a long time. A. was a pain B. hurt a lot C. was injured D. wounded me