单选题{{B}}Part C{{/B}} Economics, as we know it, is the social science concerned with the production, distribution, exchange, and consumption of goods and services. Economists focus on the way in which individuals, groups, business enterprises, and governments seek to achieve efficiently any economic objective they select. (46) {{U}}Other fields of study also contribute to this knowledge: Psychology and ethics try to explain how objectives are formed, history records changes in human objectives, and sociology interprets human behavior in social contexts.{{/U}} Standard economics can be divided into two major fields. (47) {{U}}The first, price theory or microeconomics, explains how the interplay of supply and demand in competitive markets creates a multitude of individual prices, wage rates, profit margins, and rental changes. {{/U}}Microeconomics assumes that people behave rationally. Consumers try to spend their income in ways that give them as much pleasure as possible. As economists say, they maximize utility. For their part, entrepreneurs seek as much profit as they can extract from their operations. The second field, macroeconomics, deals with modern explanations of national income and employment. Macroeconomics dates from the book, The General Theory of Employment, Interest, and Money (1935), by the British economist John Maynard Keynes. His explanation of prosperity and depression centers on the total or aggregate demand for goods and services by consumers, business investors, and governments. (48){{U}} Because, according to Keynes, inadequate total demand increases unemployment, the indicated cure is either more investment by businesses or more spending and consequently larger budget deficits by government.{{/U}} Economic issues have occupied people's minds throughout the ages. (49) {{U}}Aristotle and Plato in ancient Greece wrote about problems of wealth, property, and trade, both of whom were prejudiced against commerce, feeling that to live by trade was undesirable.{{/U}} The Romans borrowed their economic ideas from the Greeks and showed the same contempt for trade. (50){{U}} During the Middle Ages the economic ideas of the Roman Catholic church were expressed in the law of the church, which condemned the taking of interest for money loaned and regarded commerce as inferior to agriculture.{{/U}} Economics as a subject of modern study, distinguishable from moral philosophy and politics, dates from the work, Inquiry into the Nature and Causes of the Wealth of Nations (1776), by the Scottish philosopher and economist Adam Smith. Mercantilism and physiocracy were precursors of the classical economics of Smith and his 19th-century successors.

单选题For me, scientific knowledge is divided into mathematical sciences, natural sciences or sciences dealing with the natural world (physical and biological sciences), and sciences dealing with mankind (psychology, sociology, all the sciences of cultural achievements, every kind of historical knowledge). Apart from these sciences is philosophy, about which we will talk later. In the first place, all this is pure or theoretical knowledge, sought only for the purpose of understanding, in order to fulfill the need to understand that is intrinsic and con-substantial to man. What distinguishes man from animals is that he knows and needs to know. If man did not know that the world existed, and that the world was of a certain kind, that he was in the world and that he himself was of a certain kind, he wouldn"t be man. The technical aspects or applications of knowledge are equally necessary for man and are of the greatest importance, because they also contribute to defining him as man and permit him to pursue a life increasingly more truly human. But even while enjoying the results of technical progress, man must defend the primacy and autonomy of pure knowledge. Knowledge sought directly for its practical applications will have immediate and foreseeable success, but not the kind of important result whose revolutionary scope is for the most part unforeseen, except by the imagination of the Utopians. Let me recall a well-known example. If the Greek mathematicians had not applied themselves to the investigation of conic section zealously and without the least suspicion that it might someday be useful, it would not have been possible centuries later to navigate far from shore. The first men to study the nature of electricity could not imagine that their experiments, carried on because o{ mere intellectual curiosity, would eventually lead to modern electrical technology, without which we can scarcely conceive o{ contemporary life. Pure knowledge is valuable for its own sake, because the human spirit cannot resign itself to ignorance. But, in addition, it is the foundation for practical results that would not have been reached if this knowledge had not been sought disinterestedly.

单选题 The domestic economy in the United States expanded in a remarkably vigorous and steady fashion. The revival in consumer confidence was reflected in the higher proportion of incomes spent for goods and services and the marked increase in consumer willingness to take on installment debt. A parallel strengthening in business psychology was manifested in a stepped-up rate of plant and equipment spending and a gradual pickup in expenses for inventory. Confidence in the economy was also reflected in the strength of the stock market and in the stability of the bond market. For the year as a whole, consumer and business sentiment benefited from the ease in East-West tensions. The bases of the business expansion were to be found mainly in the stimulative monetary and fiscal policies that had been pursued. Moreover, the restoration of sounder liquidity positions and tighter management control of production efficiency had also helped lay the groundwork for a strong expansion. In addition, the economic policy moves made by the President had served to renew optimism on the business outlook while boosting hopes that inflation would be brought under more effective control. Finally, of course, the economy was able to grow as vigorously as it did because sufficient leeway existed in terms of idle men and machines. The United States balance of payments deficit declined sharply. Nevertheless, by any other test, the deficit remained very large, and there was actually a substantial deterioration in our trade account to a sizable deficit, almost two-thirds of which was with Japan. While the overall trade performance proved disappointing, there are still good reasons for expecting the delayed impact of devaluation to produce in time a significant strengthening in our trade picture. Given the size of the Japanese component of our trade deficit, however, the outcome will depend importantly on the extent of the corrective measures undertaken by Japan. Also important will be our own efforts in the United States to fashion internal policies consistent with an improvement in our external balance. The underlying task of public policy for the year ahead--and indeed for the longer run-- remained a familiar one.- to strike the right balance between encouraging healthy economic growth and avoiding inflationary pressures. With the economy showing sustained and vigorous growth, and with the currency crisis highlighting the need to improve our competitive posture internationally, the emphasis seemed to be shifting to the problem of inflation. The Phase Three program of wage and price restraint can contribute to reducing inflation. Unless productivity growth is unexpectedly large, however, the expansion of real output must eventually begin to slow down to the economy's larger run growth potential if generalized demand pressures on prices are to be avoided.

单选题{{B}}Part B{{/B}}{{B}}Directions:{{/B}} In the following article, some sentences have been removed. For Questions 41--45, choose the most suitable one from the list [A] – [G] to fit into each of the numbered blank. There are two extra choices, which do not fit in any of the gaps. Mark your answers on ANSWER SHEET 1. (10 points) I remember one night a few years ago when my daughter was frantic with worry. After my Harvard Extension School classes, I usually arrived at the bus station near my home by 11 p. m., but on that night I was nowhere to be found. My daughter was nervous. It wasn't safe for a single woman to walk alone on the streets at night, especially one as defenseless as I am: I can slay a mugger with my sharp wit, but I am just too short to do any real physical damage. That night my daughter checked the bus station, drove around the streets, and contacted some friends. But she couldn't find me--until she called my astronomy professor who told her that I was on top of the Science Center using the telescope to gaze at the stars. Unaware of the time, I had gotten lost in the heavens and was only thinking about the new things I had learned that night in class. This story illustrates a habit I have developed over the years: I lose track of the time when it comes to learning.{{U}} (41) {{/U}}. I may have started late; but I will continue to learn as long as I am able because there is no greater feeling, in my opinion, than traveling to a faraway country as I have and being able to identify by sight the painting of a famous artist, the statue of an obscure sculptor, the cathedral of an ancient architect.{{U}} (42) {{/U}}. So I will continue to take classes and tell my story. Lately it seems that everyone is asking me, "Mary, what advice do you have for other students?" So while I have you all here, I m going to ease my burden of answering you each individually:{{U}} (43) {{/U}}. So listen to me when I tell you this: Knowledge is power. My studies were interrupted when I was in the 7th grade, back sometime around World War I. I loved school but I was forced to leave it to care for my family. I was con-signed to work in a Rhode Island cotton mill, where I labored for many years. I eventually married and raised 5 children, 20 grandchildren, and 18 great-grandchildren. But all the while I felt inferior to those around me. I knew I was as smart as a college graduate. I knew I was capable of doing a job well— I had proved it by running a successful family business for decades that still exists. But I wanted more. I wanted to feel confident when I spoke and I Wanted people to respect my opinions. Does it surprise you to discover how much you have in common with an 89 year old woman?{{U}} (44) {{/U}}. {{U}} (45) {{/U}}. That belief is what has motivated me for the last 75 years to get this degree. It is also the mission of the Harvard Extension School. Without the support I received from this school, I might not have graduated until I was 100 -- a phrase that many of you have probably used in jest. [A] If the saying is true that wisdom comes with age,, you may safely assume that I am one of the wisest people in this hall and possibly at this university today. [B] f know that many of you graduates today, whether you were 'born in 1907 or 1967, have faced similar barriers to completing your studies and have sometimes felt inferior around those you work or socialize with just because you didn't have a degree. [C] If you have treated education as your main goal, and not as s means to an end. then you, too, have probably been claimed as a missing person once in your academic career, whether you were lost in the stars or the stacks of Widener Library. [D] But I am here today like you are--to prove that it can be done; that the power gained by understanding and appreciating the world around us can be obtained by anyone regardless of social status, personal challenges, .or age. [E] How else do you explain a woman who began high school at age 71 and who is graduating with a bachelor s degree at 89? [F] And you, too, know that the journey was worth it, and that the power of knowledge makes me the most formidable 89-year-old woman at the bus stop. [G] I have found that the world is a final exam that you can never be prepared enough for.

单选题{{B}}Text 2{{/B}} Good looks ,the video-games industry is discovering ,will get you only so far. The graphics on a modern game may far outstrip the pixellated blobs of the 1980s, but there is more to a good game than eye candy. Photo-realistic graphics make the lack of authenticity of other aspects of gameplay more apparent. It is not enough for game characters to look better—their behaviour must also be more sophisticated, say researchers working at the interface between gaming and artificial intelligence(AI). Today' s games may look better, but the gameplay is " basically the same" as it was a few years ago, says Michael Mateas, the founder of the Experimental Game Lab at the Georgia Institute of Technology. AI, he suggests, offers an" untapped frontier" of new possibilities. "We are topping out on the graphics, so what's going to be the next thing that improves game-play?" asks John Laird, director of the AI lab at the University of Michigan. Improved AI is a big part of the answer, he says. Those in the industry agree. The high-definition graphics possible on next-generation games consoles, such as Microsoft' s Xbox 360, are raising expectations across the board, says Neil Young of Electronic Arts, the world' s biggest games publisher. "You have to have high-resolution models, which requires high-resolution animation," he says," so now I expect high-resolution behaviour." Representatives from industry and academia will converge in Marina del Rey, California, later this month for the second annual Artificial Intelligence and Interactive Digital Entertainment(AIIDE) conference. The aim, says Dr Laird, who will chair the event, is to increase the traffic of people and ideas between the two spheres. "Games have been very important to AI through the years," he notes. Alan Turing, one of the pioneers of computing in the 1940s, wrote a simple chess-playing program before there were any computers to run it on; he also proposed the Turing test, a question-and-answer game that is a yardstick for machine intelligence. Even so, AI research and video games existed in separate worlds until recently. The AI techniques used in games were very simplistic from an academic perspective, says Dr. Mateas, while AI researchers were, in turn, clueless about modern games. But, he says, " both sides are learning, and are now much closer." Consider, for example, the software that controls an enemy in a first-person shooter (FPS)—a game in which the player views the world along the barrel of a gun. The behaviour of enemies used to be pre-scripted: wait until the player is nearby, pop up from behind a box, fire weapon, and then roll and hide behind another box, for example. But some games now use far more advanced" planning systems" imported from academia. "Instead of scripts and hand-coded behaviour, the AI monsters in an FPS can reason from first principles, "says Dr. Mateas. They can, for example, work out whether the player can see them or not, seek out cover when injured, and so on. "Rather than just moving between predefined spots, the characters in a war game can dynamically shift, depending on what' s happening," says Fiona Sperry of Electronic Arts. If the industry is borrowing ideas from academia, the opposite is also true. Commercial games such as" Unreal Tournament", which can be easily modified or scripted, are being adopted as research tools in universities, says Dr. Laird. Such tools provide flexible environments for experiments, and also mean that students end up with transferable skills. But the greatest potential lies in combining research with game development, argues Dr. Mateas. "Only by wrestling with real content are the technical problems revealed, and only by wrestling with technology does it give you insight into what new kinds of content are possible, "he says.

单选题Brain Cohen was an unusual kid. While other first-graders were outside playing, he was writing computer code. By junior high, he could solve Rubik"s Cube in a few minutes. A college dropout, he went on to co-found a hacker"s convention in San Francisco. "I was always really weird," he says. Yet it was only two years ago, at age 27, that he learned why. Cohen says he has trouble examining his thoughts and making eye contact but has learned to control his symptoms using behavioral psychology. Now he has a new task: warding off accusations by the Hollywood film industry that a breakthrough piece of sottware he wrote is threatening the movie business the way Napster menaced—and subsequently revolutionized—the music world. Cohen is the author of a free program called BitTorrent, which has been downloaded more than 20 million times and underpins a new generation of file-sharing technology. BitTorrent addresses a couple of the biggest problems of file sharing—that downloading bogs down when lots of folks access a file at once, and that some people leech, downloading content but refusing to share with others on the network. BitTorrent eliminates the bottleneck by having everyone share little pieces of a file at the same time—a process techies call swarming. And the program prevents leeching since folks must upload a file while they download it. All this means that the more popular the content, the more efficiently it zips through the network—bad news if you"re a movie studio trying to hinder the trading of films like The lncredibles . Says Andrew Parker of the Web-tracking firm CacheLogic, "It has turned the download world on its head." Hollywood has good reason to be worried. BitTorrent downloads account for one-third of Internet traffic, according to CacheLogic. So-called tracker sites post links to movies, video games and episodes of TV shows, the content of which is then traded at express speeds. With more folks logging onto the Internet via broadband connections, online trading of movies and TV shows is surging. Downloads of feature films alone are up 175% in the past year, says BigChampagne. In response, the Motion Picture Association of America (MPAA) recently filed dozens of civil suits against tracker sites in the U.S. and Britain, as well as criminal complaints against sites in France. The industry is hoping that in a case scheduled for next month, the U.S. Supreme Court will rule against firms that produce file-sharing software, such as Morpheus and Grokster. Neither Cohen nor BitTorrent is named in the lawsuit, although an MPAA spokesman says Cohen is under examination for continuing to develop the software "and making it easy to steal copyright material."

单选题The evolution of the mangrove species is described to______.

单选题What is the main cause of the issues in Asia according to the author?

单选题{{B}}Text 4{{/B}} A study released a little over a week ago, which found that eldest children end up, on average, with slightly higher IQ's than younger siblings, was a reminder that the fight for self-definition starts much earlier than freshman year. Families, whatever the relative intelligence of their members, often treat the firstborn as if he or she were the most academic, and the younger siblings fill in other niches: the wild one, the flirt. These imposed caricatures, in combination with the other labels that accumulate from the sandbox through adolescence, can seem over time like a miserable entourage of identities that can be silenced only with hours of therapy. But there's another way to see these alternate identities: as challenges that can sharpen psychological skills. In a country where reinvention is considered a birthright, many people seem to treat old identities the way Houdini treated padlocked boxes: something to wriggle free from, before being dragged down. And psychological research suggests that this ability can be a sign of mental resilience, of taking control of your own story rather than being trapped by it. The late-night bull sessions in college or at backyard barbecues are at some level like out-of-body experiences, allowing a re-coloring of past experience to connect with new acquaintances. A more obvious outlet to expand identity—and one that's available to those who have not or cannot escape the family and community where they're known and labeled—is the Internet. Admittedly, a lot of the role-playing on the Internet can have a deviant quality. But researchers have found that many people who play life-simulation games, for example, set up the kind of families they would like to have had, even script alternate versions of their own role in the family or in a peer group. Decades ago the psychologist Erik Erickson conceived of middle age as a stage of life defined by a tension between stagnation and generativity-a healthy sense of guiding and nourishing the next generation, of helping the community. Ina series of studies, the Northwestern psychologist Dan P. McAdams has found that adults in their 40s and 50s whose lives show this generous quality—who often volunteer, who have a sense of accomplishment—tell very similar stories about how they came to be who they are. Whether they grew up in rural poverty or with views of Central Park, they told their life stories as series of redemptive lessons. When they failed a grade, they found a wonderful tutor, and later made the honor roll; when fired From a good job, they were forced to start their own business. This similarity in narrative constructions most likely reflects some agency, a willful reshaping and re-imagining of the past that informs the present. These are people who, whether pegged as nerds or rebels or plodders, have taken control of the stories that form their identities. In conversation, people are often willing to hand out thumbnail descriptions of themselves:" I'm kind of a hermit." Or a talker, a practical joker, a striver, a snob, a morning person. But they are more likely to wince when someone else describes them so authoritatively. Maybe that's because they have come too far, shaken off enough old labels already. Like escape artists with a lifetime's experience slipping through chains, they don't want or need any additional work. Because while most people can leave their family niches, schoolyard nicknames and high school reputations behind, they don't ever entirely forget them.

单选题When Marine Lt. Alan Zarracina finally did the splits after months of struggling with the difficult pose in yoga class, the limber women around him applauded. Zarracina, a 24-year-old Naval Academy graduate and flight student, admits he would have a hard time explaining the scene to other Marines. Each class ends with a chant for peace. Then, instructor Nancy La Nasa hands students incense sticks as a gift for their 90 minutes of back bends, shoulder stands and other challenging positions. Zarracina has tried to drag some of his military friends to class, but they make fun of him. "It's not necessarily considered masculine," he said. Still, the popular classes, based on ancient Hindu practices of meditation through controlled breathing, balancing and stretching, are catching on in military circles as a way to improve flexibility, balance and concentration. A former Navy SEAL told Zarracina about the class. The August edition of Fit Yoga, the nation's second-largest yoga magazine with a circulation of 100,000, features a photo of two Naval aviators doing yoga poses in full combat gear aboard an aircraft carrier. "At first it seemed a little shocking—soldiers practicing such a peaceful art," writes editor Rita Trieger. Upon closer inspection, she said, she noticed "a sense of inner calm" on the aviators' faces. "War is hell, and if yoga can help them find a little solace, that's good," said Trieger, a longtime New York yoga instructor. Retired Adm. Tom Steffens, who spent 34 years as a Navy SEAL and served as the director of the elite corps' training, regularly practices yoga at his home in Norfolk, Va. "Once in a while I'll sit in class, and everyone is a 20-something young lady with a 10-inch waist and here I am this old guy," he joked. Steffens, who said the stretching helped him eliminate the stiffness of a biceps injury after surgery, said the benefits of regular practice can be enormous. "The yoga cured all kinds of back pains," he said. "Being a SEAL, you beat up your body." Yoga breathing exercises can help SEALs with their diving, and learning to control the body by remaining in unusual positions can help members stay in confined spaces for long periods, he said. "The ability to stay focused on something, whether on breathing or on the yoga practice, and not be drawn off course, that has a lot of connection to the military," he said. "In our SEAL basic training, there are many things that are yoga-like in nature./

单选题{{B}}Text 4{{/B}} Richard Satava, program manager for advanced medical technologies, has been a driving force bringing virtual reality to medicine, where computers create a "virtual" or simulated environment for surgeons and other medical practitioners (从业者). "With virtual reality we'll be able to put a surgeon in every trench," said Satava. He envisaged a time when soldiers who are wounded fighting overseas are put in mobile surgical units equipped with computers. The computers would transmit images of the soldiers to surgeons back in the U. S. The surgeons would look at the soldier through virtual reality helmets (头盔) that contain a small screen displaying the image of the wound. The doctors would guide robotic instruments in the battlefield mobile surgical unit that operate on the soldier. Although Satava's vision may be years away from standard operating procedure, scientists are progressing toward virtual reality surgery. Engineers at an international organization in California are developing a tele-operating device. As surgeons watch a three-dimensional image of the surgery, they move instruments that are connected to a computer, which passes their movements to robotic instruments that perform the surgery. The computer provides feedback to the surgeon on force, textures, and sound. These technological wonders may not yet be part of the community hospital setting but increasingly some of the machinery is finding its way into civilian medicine. At Wayne State University Medical School, surgeon Lucia Zamorano takes images of the brain from computerized scans and uses a computer program to produce a 3-D image. She can then maneuver the 3-D image on the computer screen to map the shortest, least invasive surgical path to the tumor (肿瘤). Zamorano is also using technology that attaches a probe to surgical instruments so that she can track their positions. While cutting away a tumor deep in the brain, she watches the movement of her surgical tools in a computer graphics image of the patient's brain taken before surgery. During these procedures--operations that are done through small cuts in the body in which a miniature camera and surgical tools are maneuvered--surgeons are wearing 3-D glasses for a better view. And they are commanding robot surgeons to cut away tissue more accurately than human surgeons can. Satava says, "We are in the midst of a fundamental change in the field of medicine."

单选题{{B}}Text 2{{/B}} Like street comer prophets proclaiming that tile end is near, scientists who study the earth's atmosphere have been issuing predictions of impending doom for the past few years without offering any concrete proof. So far even the experts have had to admit that no solid evidence has emerged that this is anything but a natural phenomenon. And the uncertainty has given skeptics-especially Gingrichian politicians--plenty of ammunition to argue against taking the difficult, expensive steps required to stave off a largely hypothetical calamity. Until now, A draft report currently circulating on the Internet asserts that the global temperature rise can now be blamed, at least in part, on human activity. Statements like this have been made before by individual researchers-who have been criticized for going too far beyond the scientific consensus. But this report comes from the International Panel on Climate Change (IPCC), a respected UN sponsored body made up of more than 1,300 leading climate experts from 40 nations. This shift in scientific consensus is based not so much on new data as on improvements in the complex computer models that climatologists use to test their theories. Unlike chemists or molecular biologists, climate experts have no way to do lab experiments on their specialty. So they simulate them on supercomputers and look at what happens when human generated gases-carbon dioxide from industry and auto exhaust, methane from agriculture, chlorofluoro carbons from leaky refrigerators and spray cans-are pumped into the models virtual atmospheres. Until recently, the computer models weren't working very well. When the scientists tried to simulate what they believe has been happening over the past century or so, the results didn't mesh with reality; the models said the world should now he warmer than it actually is. The reason is that the computer models had been overlooking an important factor affecting global temperatures: sulfur dioxides that are produced along with CO2 when fossil fuels are burned in cars and power plants. Aerosols actually cool the planet by blocking sunlight and mask the effects of global warmning. Once the scientists factored in aerosols, their models began looking more like the real world. The improved performance of the simulations was demonstrated in 1991, when they successfully predicted temperature changes in the aftermath of the massive Mount Pinatubo eruption in the Philippines. A number of studies since have added to the scientists confidence that they finally know what they are talking about-and can predict what may happen if greenhouse gases continue to be pumped into the atmosphere unchecked.

单选题As with many a grown-up sporting star, the first hint of greatness came at an early age for Lewis Hamilton. As an eight-year-old at his first kart race, he charged "more like a mature driver than a novice," remembers Martin Hines, owner of the Zip Kart racing company. Scything his way through the field just outside London, Hamilton had a confident style that seemed different from normal rookies, Hines says. "There was a little spark about him." Now 22, and in his debut season in Formula One—he became the first black driver to make it onto the grid in motor racing's blue-ribbon championship. His success and profile that have earned young Hamilton comparisons with other sporting greats. His color— Hamilton's grandfather came to Britain from Grenada in the 50s—and the positive influence of his father, Anthony, have drawn parallels with Tiger Woods. Hamilton acknowledges that his participation could stoke interest among ethnic groups who may not be into the sport now. "Hopefully people that can relate to me will see that it's possible and also try to get into the sport," he told the BBC. Moreover, his youth, good looks and wholesome image are also likely to get marketers fired up. Countless more karting titles followed before 2001. He "made seasoned drivers look silly," says Tony Shaw, Hamilton's then team manager at Manor Motorsport. Hamilton's raw, natural speed and canny race craft nudged him closer to the big leagues. Hamilton's "understanding of when and where to overtake and how to take advantage of a situation is very advanced," Shaw says. At his first crack at GP2, the training ground for Formula One, Hamilton dominated the 2006 season with a series of blistering drives on his way to the title. Hamilton is "not worried about showing or doing what he's used to doing just because it's Formula One," says Hill. For many new drivers, "that's an enormous hurdle." With the retirement last year of seven-time world champion Michael Schumacher, there's one less rival for Hamilton to negotiate. And Hamilton is certainly not short on confidence. When he first met Ron Dennis—now his Formula One team boss—as a 10-year-old in a borrowed suit, Hamilton promptly told him he wanted to drive for McLaren. Three years later, he joined the team's support program for promising young drivers. But, say former team managers, he's ready to listen and learn when things go wrong. Hamilton has a rare "capacity to question himself—to analyze very clearly after a race," says Frederic Vasseur, general manager at the ART Grand Prix team behind Hamilton's GP2 championship. As for whether he'll become the Tiger Woods of the sport, it's too early to know whether he can live up to those standards. But for now, his fans are bullish. Damon Hill was the last British driver to take the world crown. And it's Hamilton, Hill says, "who looks likely to be the next./