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Competition for admission to the country’s top private schools has always been tough, but this year Elisabeth realized it had reached a new level. Her wake-up call came when a man called the Dalton School in Manhattan, where Elisabeth is admissions director, and inquired about the age cutoff for their kindergarten program. After providing the information, she asked about the age of his child. The man paused for an uncomfortably long time before answering. “Well, we don’t have a child yet. We’re trying to figure out when to conceive a child so the birthday is not a problem.”Worries are spreading from Manhattan to the rest of the country. Precise current data on private schools are unavailable, but interviews with representatives of independent schools all told the same story: an oversupply of applicants, higher rejection rates. “We have people calling us for spots two years down the road,” said Marilyn of the Seven Hills School in Cincinnati. "We have grandparents calling for pregnant daughters." Public opinion polls indicate that Americans’ No. 1 concern is education. Now that the long economic boom has given parents more disposable income, many are turning to private schools, even at price tags of well over $10000 a year. “We’re getting applicants from a broader area geographically than we ever have in the past,” said Betsy of the Latin School of Chicago, which experienced a 20 percent increase in applications this year.“The problem for the applicants is that while demand has increased, supply has not.” Every year, there are a few children who do not find places, but this year, for the first time that I know of, there are a significant number without places,” said Elisabeth.So what can parents do to give their 4-year-old an edge? Schools know there is no easy way to pick a class when children are so young. Many schools give preference to children of their graduates. Some make the choice by drawing lots. But most rely on a mix of subjective and objective measures: tests that at best identify developmental maturity and cognitive potential, interviews with parents and observation of applicants in classroom settings. They also want a diverse mix. Children may end up on a waiting list simply because their birthdays fall at the wrong time of year, or because too many applicants were boys.The worst thing a parent can do is to pressure preschoolers to perform—for example, by pushing them to read or do math exercises before they’re ready. Instead, the experts say, parents should take a breath and look for alternatives. Another year in preschool may be all that’s needed.16. From this text we learn that it is .17. The sentence “We have people....down the road” (Paragraph 2) probably means .18. The text indicates that private schools are very selective because they .19. From the text, we can infer that author .20. Which of the following can serve as a Title of this text?

All societies have distinct role expectations for men and for women. In the United States, these expectations have been undergoing change for many decades. Today Americans live in a world of diverse family patterns and conflicting images of ideal life styles for men and women. The conventional norms of the first half century defined a successful woman as a wife and mother who stayed home to carry out a full array of household duties. The husband and father was expected to stay away from the home most of the day, earning enough money to pay the bills. Many adults still live by these expectations, but the traditional pattern is no longer held up as an ideal to be followed by everyone. Times have changed; there is no return to yesterday.Although the women’s movement and political controversies about such issues and the Equal Rights Amendment and sexual harassment suggest that changing sex roles is a recent issue, this is far from the case. Broad trends can be identified over the past hundred years. Women have increased their participation in the labor force from 18% in 1900 to over 50% today, and they give birth to fewer children than women did in the past. In 1910 the birth rate was 30 per 1,000 population; by the 1900s it had declined to 16 per 1,000. These two trends—increasing participation in the labor force and decreasing family size—suggest that major long-term changes have restructured the role expectations of men and women. These changes are complex. The fact that more women are joining the labor force as full-time workers does not mean that a single sex role pattern is emerging.On the contrary, we are living in a period of diverse family patterns. According to Kathleen Gerson, “the domestic woman who builds her life around children and homemaking persists, but she now coexists with a growing number of working mothers and permanently childless women.”Women today face hard choices as they make decisions about work, career, and motherhood. Despite women’s liberation, women still earn less than men in the work place and are still expected to do most of the work in the home. Women work substantially more hours each week in the home and at the workplace than men do. Women are working harder than ever, yet many do not enjoy the benefits of full equality.11. The tradition roles for men and women .12. Changing sex roles is not a recent issue because .13. The fact that more women are joining the labor force as full time workers means that .14. It’s stated in the last paragraph that .15. According to this passage, the statement which is NOT true is __.

Researchers at UCLA Medical Center in Los Angeles, California found that a 12-minute bedside visit with a dog can help ease anxiety levels by 24 percent in heart failure patients, compared to a 10 percent drop when patients had a visit from a human volunteer, and no drop in patients who had no visit.Results of the 76-patient study were presented last week at the American Heart Association’s annual Scientific Sessions in Dallas, Texas. The study was funded by the Pet Care Trust Foundation, a non-profit organization which promotes human-animal interaction and bonding. In the study, effects of dog and volunteer visits were compared with those of volunteers only, and with patients who had no visits and remained at rest. Heart pressures were monitored and patients were asked to answer a list of anxiety assessment questions before and after the visits. Although critical pressure measures also decreased, suggesting improved cardiac function, the most marked response was seen in anxiety levels.“The first thing you notice is that the patient’s facial expression changes to a smile and the stress of the world seems to be lifted off their shoulders,” study author Kathy Cole said. Feelings of depression and helplessness are common among heart patients, Cole said, and just three nights in a hospital is enough to make some patients feel anxious and unsettled. During the visit, the furry friend is allowed to lie on the bed next to the patient with its head within two feet of the patient’s. Most patients petted the dog, while others engaged human volunteers in conversation about the dog.Dogs used in the study are specially trained animal-assisted therapy dogs that undergo a series of trainings, evaluations and certifications to qualify as therapy dogs. Dog breeds varied. Researchers used everything from Bernese mountain dogs to small schnauzers. However, a dog doesn’t have to be specially trained to have a calming effect on its human counterparts. In fact, the animal doesn’t even have to be a dog in order to help. “As long as the animal has meaning to the patient, or a relationship with the patient, it can help calm the patient,” Cole said.6. We learn from the text that heart patients benefit most from visits .7. The study shows that, for heart patients, .8. According to Cole, the change of patients’ facial expression indicates that .9. Cole believes that dogs are helpful to the patients if .10. This report focuses on __.

Back in the early 1990s, I knew little about computers beyond what it took to get through a working day. But here’s what I did know: something huge was happening. It was stirring economies and imaginations and possibilities like nothing I had ever known. I knew the world was changing in ways that meant I shouldn’t count on old assumptions. And I knew I had dreams I still hadn’t fulfilled. But I didn’t know how to realize them until I met with my old friend, Rolly Rouse, when we happened to move into the same neighborhood.Rolly often called me with a stream of ideas. His rate of idea production per second seemed almost incredible. Soon we were on the phone with each other every day. Talking about the Internet. Talking about starting a new online company—maybe together.He was then developing a plan and he wanted me to be a part of it: we would give people wonderful, whole electronic houses on a CD-ROM and let them modify those homes to their own needs. Try out different windows and doors, different paint colors and furnishings. When they were satisfied, we would enable them to go online to make the project happen, to get the products and the financing and the professional design and construction to help to do it outright.BuildingBlocks was the name Rolly came up with for his new enterprise. Rolly took the plunge first. He simply dropped his profitable energy-consulting business to commit himself full time to BuildingBlocks. I soon joined him after I quit my well-paid job at a newspaper.Together we developed a demo to show the features of our CD-ROM, “The New American Dream Home”. Then we took it to the annual convention of the National Association of Home Builders in Boston. All the big companies were there showing off their latest products.To our delight, nearly everyone was eager to see what we were showing, including the top executives of some enormous companies. When we left, we had invitations from them to come to their offices to tell them more about BuildingBlocks.That was the start of my real lifetime dream and BuildBlocks, our company, has been prospering ever since.1. By “something huge was happening”, the writer refers to .2. The text shows that Rolly Rouse is .3. BuildingBlocks is a company that helps people to .4. Rolly and the writer decided to start a company together because they were both .5. At the Boston convention, Rolly and the writer were happy because __.

在不久的将来，3D打印技术将走进千家万户。有了 3D打印机后，人人都可以通过数码设计制造出各种想象中的物体，或者借用不管来自世界哪个角落的某种设计。只需按一个钮，3D打印机就可以用一层层的塑料或其它材质，把你设计的物品在你眼前“打印”出来。10年前的科幻小说情节如今己经成为现实。事实上，能让我们的电脑打印纸质文档的点矩阵(dot-matrix)打印机，这是不久之前才发明出来的，而现在3D打印机又以同样的方式，使我们梦想的各种物体都能呈现在我们眼前。有了 3D打印机的魔力，人人都是制造商，唯一能限制我们的，就是我们的想象力。

很多人认为没有兄弟姐妹的孩子很幸运，因为他们可以得到物质享受和别人的注意。但是想一想独生子女没有隐私---父母总是感觉自己有权知道发生在他或她生活中的一切。身为独生子女的第二个缺点是缺少某些优势，而这恰恰是有兄弟姐妹的孩子所拥有的。独生子女无法因为事情出错而责备兄弟姐妹，或是索要哥哥姐姐以前曾被给予的特权。此外，独生子女也失去了兄弟姐妹的陪伴。结果就是孤独，以及在日后的生活中交朋友也会遇到麻烦，因为他们从未学过与兄弟或姐妹相处。

For a century or so, the shopping ritual at dealer showrooms for new and used vehicles hasn’t changed much, apart from more comfortable chairs and the addition of latte (拿铁咖啡) machines.But the Internet is unraveling the essence of new-car retailing, arming shoppers with more information than ever about features and prices, and (as) well as expert reviews. Will shoppers soon be able to take the next step and order new cars online, like books, laptops and shoes?The debate over Internet vehicle sales rages, since automakers see if (it) as a way to slash distribution costs by hundreds, and perhaps a few thousand dollars per vehicle. Dealers are aghast: They have shielded their franchises in every state with legislation. Many view Internet sales as a means of undermining them. Dealers assert that “cars aren’t books or shoes” and are best sold in person by their sales staff, a process that allows the shopper to test the vehicle, as well as explore financing and trade-ins.Tesla Motors (TSLA.，the groundbreaking electric-vehicle manufacturer founded by Elon Musk, takes orders for its Model S sedan, which starts at $70.000, on its website. The cars are delivered either at one of its 30 company-owned stores or can be drop-shipped to a buyer’s home. Tesla, clearly, is bucking law and tradition. “In Texas, where the law precludes delivering directly to customers, we do so through third-parties,” said Sharma Hendriks, a Tesla spokesperson. “We’re not saying we’ll never have dealers; but that model doesn’t make sense for us now.Because the market for used cars isn’t protected by new-car franchise laws, it may provide a more promising opportunity for online vehicle sales. eBay Motors, a division of eBay (EBAY), offers thousands of vehicles online for sales between private parties. Many used-car dealers also use the digital platform and pay a listing fee.Carvana, a venture sponsored by DriveTime, one of the nation’s largest used-car operations, has begun selling late-model used premium and luxury models on its own website. Carvana operates for the time being only in Atlanta and its environs but hopes to expand nationwide.Ernie Garcia Jr., Carvana’s chief executive officer, said that the first hundred vehicles sold by Carvana reflect what he called a “promising” trend of high satisfaction among buyers. Four buyers of the first hundred weren’t satisfied with their purchase and exercised their right to trade the vehicles they bought for another. Only one of the hundred demanded a refund.Garcia said that sales of new and used vehicles at dealerships, in the conventional manner, reflect about “$2,000 a car” in sales, general and administrative cost. He regards that amount as margin that can and will eventually shrink as online attracts more vehicle shoppers. New-vehicle sales online haven’t arrived, and perhaps may never. Yet that day feels as though it’s drawing closer, especially for consumers who will choose anything and everything-including a spouse-using keypad or mouse.For a century or so, the shopping ritual at dealer showrooms for new and used vehicles hasn’t changed much, apart from more comfortable chairs and the addition of latte （拿铁咖啡） machines.

On the first day of the US federal government shutdown, a Californian resident may not yet feel the impact, but many Chinese tourists are unhappy and their tour guides nervous. Tony Lu has run a travel agency in Los Angeles for 20 years. Four tourist groups from China’s mainland organized by his agency are currently travelling around the United States. They are suffering different kinds of impact from the federal government shutdown, which led to the close of 401 national parks, Smithsonian’s 19 museums and galleries and the National Zoo. “Compared to the 1995-1996 shutdown, this time is more serious to us. We run mostly Chinese market business and there are many more Chinese tourists groups now than 17 years ago,” he said.“Our clients are complaining. The tour guides explained to them that even the US President Barack Obama cannot solve the problem immediately,” he said. Some of the groups have to change their itineraries (行程)as they cannot enter Yellowstone National Park or the Lincoln Memorial, nor can they have a close look of the Statue of Liberty, all of which are among the most popular tourism sites.According to National Park Services, the national parks have about 715,000 visitors per day on average in October. But now, visitors are being turned away.Although there’s no figure yet of how many Chinese tourists are affected by the shutdown, some are expressing their sadness online. “I want to cry,” wrote Ms He to her WeChat (微信)friends. She had been looking forward to her sightseeing trip to the US for a long time.But soon after she landed, she learned that the Statue of Liberty, Lincoln Memorial and many other tourist attractions on her list would be closed.“Nobody will give any compensation to these Chinese tourists. The Senate and the Congress will definitely not,” said Lu, “And we have to do more to make them feel better, such as explaining the situation to them and helping some of them modify their travel plans. Hopefully the federal government shutdown ends soon.”Nearly 1.5 million Chinese traveled to the US last year, according to the Office of Travel and Tourism Industries of the US Department of Commerce.Chinese companies doing business in the US may also be affected if the federal regulatory agencies and other services do not resume work soon.

Criticism is a valuable means of helping ourselves and others achieve personal growth. However, because it is often done carelessly or cruelly, criticism has a bad reputation. Here are some guidelines for offering criticism constructively. First, wait until the person asks for feedback on his or her performance or actions. Unasked-for criticism is not usually valuable. Second, describe the person’s behavior as specifically as possible before you criticize it. Instead of just saying, “You were awful,” tell the person exactly what you observed. And finally, try to balance your criticism with positive statements. Look for significant points in the other person’s performance that you can honestly praise.

Ideas about education are changing in the United States. Education today is not just a high school diploma or a college degree. Many adults are not interested in going to college. They are interested in other kinds of learning. For them, learning does not end with a diploma.Continuing education gives these adults the opportunity to increase their knowledge about their own field or to learn about a new field. It also gives them a chance to improve their old skills or to learn new ones.Secretaries, mechanics, and barbers can take classes to improve their work skills. Nurses can take classes to increase their knowledge of nursing. If they know more or learn more, then they can get a better job or earn more money.Continuing education classes give some adults the chance to learn new skills. There is usually a large variety of classes to choose from, typing, foreign cooking, photography, auto repair, furniture repair, or swimming. These are only some of the classes available.Some adults take classes for fun or because the class will be useful for them. For example, they can choose a class in almost any language, Chinese, Spanish or English as a second language. There are classes in first aid or classes in sewing. There are also many other types of classes to choose from.Other adults take continuing education classes to improve their own lives because they want to feel better about themselves. Overweight people can find exercise classes or classes in nutrition. Others can learn how to be good parents, or how to get along with other people. There are many opportunities for adults to continue their learning. Almost any community college or public school system has a continuing education program. There are classes in schools, community buildings, or churches. Most classes are in the evening, so working people can attend. The classes are usually small, and they are inexpensive.Thousands of people register for continuing education classes each year. They receive no diploma or certificate, and no grade for most of the classes they attend. For them, learning is something they do because they want to.1.Lots of people attend continuing education classes because（） .2.Some adults take lessons of typing or auto repair to （）.3.What’s the main idea of Para.7?4.Attending continuing education classes（） .5.We can learn from the passage that（） .

The way people hold to the belief that a fun-filled, pain free life equals happiness actually reduces their chances of ever attaining real happiness. If fun and pleasure are equal to happiness, then pain must be equal to unhappiness. But in fact, the opposite is true; more often than not things that lead to happiness involve some pain.As a result, many people avoid the very attempts that are source of true happiness. They fear the pain inevitably brought by such things as marriage, raising children, professional achievement, religious commitment, or self-improvement.Ask a bachelor why he resists marriage even though he finds dating to be less and less satisfying. If he is honest he will tell you that he is afraid of making a commitment. For commitment is in fact quite painful. The single life is filled with fun, adventure, and excitement. Marriage has such moments, but they are not its most distinguishing features.Couples with infant children are lucky to get a whole night’s sleep or three-day vacation. I don’t know why any parent who would choose the word fan to describe raising children. But couples who decide not to have children never know the joys of watching a child grow up or of playing with a grandchild.Understanding and accepting that happiness has nothing to do with fun is one most liberating realization. It liberates time: now we can devote more hours to activities that can genuinely increase our happiness. It liberates money: buying that new car or those fancy clothes that will do nothing to increase our happiness now seems pointless. And it liberates us from envy: we now understand that all those who are already having so much fun actually may not be happy at all.1.To understand what true happiness is one must（） .2.According to the author, a bachelor resists marriage chiefly because （）.3.Raising children, in the author’s opinion, is （）.4.From the last paragraph, we learn that envy sometimes stems from（） .5.What is the main point the author is going to tell us?

The first ancient Olympics were held in 776 B.C. The games got their name from Olympia, the Greek city where they took place. Like the summer Olympics of today, the ancient Olympics were held every four years.Thousands of people from all over the Greek world came to watch. The main stadium held about 45,000 people. “We have accounts of visitors and pilgrims setting up tents all around the site.” Lisa Cerrato of Tufts University said.During the first Olympics, there was only one competition-a 200-meter race. But over time the games grew to include wrestling, racing, boxing, and other sports. Women were not allowed to compete, but they had their own separate games.“The ancient athlete became celebrities, just like today. They often lived the rest of their lives being treated to free dinners.” Cerrato said, “City-states even tried to steal away each other’s athletes by offering them various awards.”The ancient Olympics existed until A. D. 393. But the modem Olympics are still going strong.1.Where did the ancient Greeks hold their first Olympics?2.How did researchers know that ancient Greeks rushed to watch the Olympics?3.What did women do since they were not allowed to participate in the Olympics?4.The ancient athletes must have felt honored when they （）.5.It can be inferred from the fourth paragraph that （）.

These days a green building means more than just the color of the paint. Green buildings can also refer to environmentally friendly houses, factories, and offices.Buildings account for 65 percent of total U.S electricity use. But green buildings can reduce energy and water use. Also, the buildings are often located near public transportation such as buses and subways, so that people can drive their cars less. That could be good for the environment, because cars use lots of natural resources such as gasoline, and give off pollution. Green buildings are often built on previously developed land, so that the buildings don’t destroy forests or other wild habitats.Marty Dettling is project manager for a building that puts these ideas into action. The Solaire has been called the country’s first green residential high-rise building. According to Dettling, “We’ve reduced our energy consumption by one-third and our water by 50 percent.” Not everyone is leaping to move into a green building, however. Some people think that features such as solar panels cost more money than more traditional energy sources. Despite this, Dettling hopes that green buildings will become common in the future. “It’s going to be big,” she said.1.What do green buildings refer to nowadays?2.The word “Also” (line 2, Para. 2) is used to（） .3.In terms of land use, green buildings are constructed by（） .4.Why are some people NOT so interested in green buildings?5.What did Marty Dettling mean when she said “It’s going to be big”?

I’ve been writing for most of my life. The book Writing Without Teachers introduced me to one distinction and one practice that has helped my writing processes tremendously. The distinction is between the creative mind and the critical mind. While you need to employ both to get to a finished result, they cannot work in parallel no matter how much we might like to think so.Trying to criticize writing on the fly is possibly the single greatest barrier to writing that most of us encounter. If you are listening to that 5th grade English teacher correct your grammar while you are trying to capture a fleeting thought, the thought will die. If you capture the fleeting thought and simply share it with the world in raw form, no one is likely to understand. You must learn to create first and then criticize if you want to make writing the tool for thinking that it is.The practice that can help you past your learned bad habits of trying to edit as you write is what Elbow calls “free writing.” In free writing the objective is to get words down on paper non-stop, usually for 15-20 minutes. No stopping no going back. No criticizing. The goal is to get the words flowing. As the words begin to flow, the ideas will come out from the shadows and let themselves be captured on your notepad or your screen.Now you have raw materials that you can begin to work with using the critical mind that you’ve persuaded to sit on the side and watch quietly. Most likely, you will believe that this will take more time than you actually have and you will end up staring blankly at the page as the deadline draws near.Instead of staring at a blank screen start filling it with words no matter how bad. Halfway through your available time, stop and rework your raw writing into something closer to finished product. Move back and forth until you run out of time and the final result will most likely be far better than your current practices.1.When the author says the creative mind and the critical mind “cannot work in parallel”(Line 4 Para. 1) in the writing process, he means（） .2.What prevents people from writing on is（） .3.What is the chief objective of the first stage of writing?4.One common concern of writers about “free writing” is that（） .5.In what way does the critical mind help the writer in the writing process?

In a country that defines itself by ideals, not by shared blood, who should be allowed to come, work and live here? In the wake of the Sept 11 attacks these questions have never seemed more pressing.On Dec. 11, 2001, as part of the effort to increase homeland security, federal and local authorities in 14 states staged “Operation Safe Travel”一raids on airports to arrest employees with false identification. In Salt Lake City there were 69 arrests. But those captured were anything but terrorists, most of them illegal immigrants from Central or South America. Authorities said the undocumented workers’ illegal status made them open to blackmail by terrorists.Many immigrants in Salt Lake City were angered by the arrests and said they felt as if they were being treated like disposable goods.Mayor Anderson said those feelings were justified to a certain extent, “We’re saying we want you to work in these places, we’re going to look the other way in terms of what our laws are, and then when it’s convenient for us, or when we can try to make a point in terms of national security, especially after Sept. 11, then you’re disposable. There are whole families being uprooted for all of the wrong reasons,” Anderson said.If Sept. 11 had never happened, the airport workers would not have been arrested and could have gone on quietly living in America, probably indefinitely. Ana Castro, a manager at a Ben & Jerry’s ice cream shop at the airport had been working 10 years with the same false Social Security card when she was arrested in the December airport raid. Now she and her family are living under the threat of deportation, Castro’s case is currently waiting to be settled. While she awaits the outcome, the government has granted her permission to work here and she has returned to her job at Ben & Jerry’s.1.According to the author, the United States claims to be a nation （）.2.How did the immigrants in Salt Lake City feel about “Operation Safe Travel?3.Undocumented workers became the target of “Operation Safe Travel” because（） .4. By saying we’re going to look the other way in terms of what our laws are” (Line 2,Para. 4), Mayor Anderson means “ （）5.What do we learn about Ana Castro from the last paragraph?

Communications technologies are far from equal when it comes to conveying the truth. The first study to compare honesty across a range of communication media has found that people are twice as likely to tell lies in phone conversations as they are in emails. The fact that emails are automatically recorded-and can come back to haunt （困扰）you—appears to be the key to the finding.Jeff Hancock of Cornell University in Ithaca, New York, asked 30 students to keep a communications diary for a week. In it they noted the number of conversations or email exchanges they had lasting more than 10 minutes, and confessed to how many lies they told. Hancock then worked out the number of lies per conversation for each medium. He found that lies made up 14 per cent of emails, 21 percent of instant messages, 27 per cent of face-to-face interactions and an astonishing 37 per cent of phone calls.His results to be presented at the conference on human-computer interaction in Vienna, Austria, in April, have surprised psychologists. Some expected emailers to be the biggest liars, reasoning that because deception makes people uncomfortable, the detachment of emailing would make it easier to lie. Others expected people to lie more in face-to-face exchanges because we are most practiced at that form of communication.But Hancock says it is also crucial whether a conversation is being recorded and could be reread and whether it occurs in real time. People appear to be afraid to lie when they know the communication could later be used to hold them to account, he says. This is why fewer lies appear in email than on the phone.People are also more likely to lie in real time-in an instant message or phone call, say-than if they have time to think of a response, says Hancock. He found many lies are spontaneous responses to an unexpected demand, such as: “Do you like my dress?”Hancock hopes his research will help companies work out the best ways for their employees to communicate. For instance, the phone might be the best medium for sales where employees are encouraged to stretch the truth. But, given result, work assessment where honesty is a priority, might be best done using email.1.Hancock’s study focuses on（） .2.Hancock’s research finding surprised those who believed that（） .3.According to the passage, why are people more likely to tell the truth through certain media of communication?4.According to Hancock the telephone is a preferable medium for promoting sales because（）5.It can be inferred from the passage that（） .

You never see him, but they’re with you every time you fly. They record where you are going, how fast you’re traveling and whether everything on your airplane is functioning normally. Their ability to withstand almost any disaster makes them seem like something out of a comic book. They're known as the black box.When planes fall from the sky, as a Yemeni airliner did on its way to Comoros Islands in the India ocean June 30, 2009, the black box is the best bet for identifying what went wrong. So when a French submarine detected device’s homing signal five days later, the discovery marked a huge step toward determining the cause of a tragedy in which 152 passengers were killed.In 1958, Australian scientist David Warren developed a flight-memory recorder that would track basic information like altitude and direction. That was the first mode for a black box, which became a requirement on all U.S. commercial flights by 1960. Early models often failed to withstand crashes, however, so in 1965 the box was completely redesigned and moved to the back of the plane - the area least affected by impact-from its original position in the landing wells (起落架舱).The same year, the Federal Aviation Authority required that the boxes, which were never actually black, be painted orange or yellow to be discovered more easily.Modem airplanes have two black boxes: a voice recorder, which tracks pilots’ conversations, and a flight-data recorder, which monitors fuel levels, engine noises and other operating functions that help investigators reconstruct the aircraft’s final moments. Placed in an insulated case and surrounded by a quarter-inch-thick panels of stainless steel, the boxes can withstand massive force and temperatures up to 2,000'F. When submerged, they’re also able to emit signals from depths of 20,000ft. Experts believe the boxes from Air France Flight 447, which crashed near Brazil on June 1.2009, are in water nearly that deep, but statistics say they're still likely to turn up. In the approximately 20 deep-sea crashes over the past 30 years, only one plane’s black boxes were never recovered.1.What does the author say about the black box?2.What information could be found from the black box on the Yemeni airliner?3.Why was the black box redesigned in 1965?4.Why did the Federal Aviation Authority require the black boxes be painted orange or yellow?5.What do we know about the black boxes from Air France Flight 447?

二十多年前科学家就己经知道癌症是一种基因病变。细胞核(nucleus)内的DNA被某种物质打乱，细胞突然不再有规则地分裂，而开始大量复制自身。不同于普通细胞的是，这种复制活动永无休止。癌症细胞和正常细胞差异极大，要理清造成这种差异的事件的先后顺序几乎是不可能的，所以很多年来研究人员一直在攻关这一难题，通过研究健康细胞，他们试图确定是什么变化使得这些健康细胞变成了癌细胞，但却总是以失败告终。现在情况出现了转机。根据最近的一期《自然》杂志刊载的报道，麻省理工学院的生物医学研究所的一个科研小组终于成功地将人类细胞转变为恶性(malignant)细胞。他们采用了两种不同的细胞类型，通过把三种经过改变的基因嵌入这些细胞的DNA中，从而取得这一成就。虽然这些操作都只是在实验室的器皿里完成的，不会立刻带来任何治疗方法，但显然它们是理解这种疾病的关键一步。

过去十年间，中国手机网络的发展可谓有目共睹，几乎每年都会新增约八千万用户，但据英国广播公司报道，在某种程度上，真正的通讯革命才刚刚开始。今年，中国将取代美国成为世界最大的智能手机市场。对很多中国人来说，智能手机使他们第一次拥有了通向互联网的私人路径。这对于信息技术开发商、尤其是移动手机应用程序开发商来说是非比寻常的机遇。那么，应用程序开发商是怎么在中国赚到钱的呢？一种方法就是尝试“应用内销售” 一一他们推出免费的应用程序，一旦用户被吸引，再以较低的价格卖给他们体验增强版。虽然中国的用户只愿意出几分钱来购买升级服务，但只要想想用户多达数百万，加在一起很快就是一大笔钱。不过，对于非游戏类应用程序开发商来说，要发展就得依靠广告收益。

The miniaturization of the components of computer chips has proved unstoppable. In each new generation, those components are smaller and more tightly packed than they were in its predecessor. Progress has been so rapid that chip designers are approaching apparently fundamental barriers to further reductions in size and increases in density. One of these is imposed by the need to wire the components in a chip together, so that they can exchange signals. But, in a miniaturized version of the shift to wireless communication in the macroscopic world, a group of researchers led by Alain Nogaret of the University of Bath, in England, think they can make chips whose components talk to each other wirelessly.At present, the electronics that transmit and receive the radio waves used in wireless devices are too large to be used within individual chips. But Dr Nogaret believes he can overcome this. Last week he and his colleagues at three other British universities, another in Belgium and a research institute in France won the money to try to build such a device.The researchers intend to use the standard lithographic（平印刷板）techniques employed in chipmaking to coat a semiconductor with microscopic magnets. These magnets will generate local magnetic fields that point in opposite directions at different points on the chip's surface. Electrons have a property called spin that is affected by magnetic fields, and the team hopes to use an effect called inverse electron-spin resonance（谐振）to make electrons passing through the chip emit microwaves. .The technique they are proposing is the reverse of the process in medical magnetic-resonance imaging. In MRI, the patient is placed in a strong magnetic field that causes some of his body atomic nuclei, which act like tiny magnetized spinning tops, to align themselves with the field. The nuclei are then zapped briefly with a second magnetic field that knocks them out of alignment with the first one. The coils in the scanning apparatus detect these magnetic changes, which are used to build up a map of the part of the body being examined. After a few seconds, the nuclei themselves with the field, radiating small amounts of energy as heat or, more rarely, as radio waves.In chips, Dr Nogaret proposes to use the spin of the electron rather than the spin of the atomic nucleus. Electrons flowing through the chip would “see” a magnetic field that flips from one direction to the opposite every few hundred nanometres (billionths of a metre). This is the equivalent of zapping to the stationary object with an oscillating magnetic field of the sort used in MRI. The changing magnetic field would force the electrons to oscillate, too, but would not allow them to radiate heat. As a result, they would be forced to emit radio waves— or, rather, microwaves, which are similar but of shorter wavelength.

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