Eat More, Weigh Less, Live Longer Clever genetic detective work may have found out the reason why a near-starvation diet prolongs the life of many animals. Ronald Kahn at Harvard Medical School in Boston, US, and his colleagues have been able to extend the lifespan (寿命) of mice by 18 per cent by blocking the rodent’s (啮齿动物) increase of fat in specific cells. This suggests that thinness--and not necessarily diet--promotes long life in “calorie (热量卡) restricted“ animals. “It’s very cool work,“ says aging researcher Cynthia Kenyon of the University of California, San Francisco. “These mice eat all they want, lose weight and live longer. It’s like heaven.“ Calorie restriction dramatically extends the lifespan of organisms as different as worms and rodents. Whether this works in humans is still unknown, partly because few people are willing to submit to such a strict diet. But many researchers hope they will be able to trigger the same effect with a drug once they understand how less food leads to a longer life. One theory is that eating less reduces the increase of harmful things that can damage cells. But Kahn’s team wondered whether the animals simply benefit by becoming thin. To find out, they used biology tricks to disrupt the insulin (胰岛素) receptor (受体) gene in lab mice--but only in their fat cells. “Since insulin is needed to help fat cells store fat, these animals were protected against becoming fat,“ explains Kahn. This slight genetic change in a single tissue had dramatic effects. By three months of age, Kahn’s modified mice had up to 70 per cent less body fat than normal control mice, despite the fact that they ate 55 per cent more food per gram of body weight. In addition, their lifespan increased. The average control mouse lived 753 days, while the thin rodents averaged a lifespan of 887 days. After three years, all the control mice had died, but one-quarter of the modified rodents were still alive. “That they get these effects by just manipulating the fat cells is controversial,“ says Leonard Guarente of the Massachusetts Institute, of Technology, who studies calorie restriction and aging. But Guarente says Kahn has yet to prove that the same effect is responsible for increased lifespan in calorie-restricted animals. “It might be the same effect or there might be two routes to long life,“ he points out, “and that would be very interesting.“Ronald Kahn and his colleagues can make mice live longer by offering them less food. giving them a balanced diet. disrupting the specific genes in their fat cells. preventing them growing larger.

Her treatment of the subject is exhaustive. very boring very thorough very interesting very touching

Our lives are intimately bound up with theirs. tensely nearly carefully closely

The industrial revolution modified the whole structure of English society. destroyed broke changed smashed

He rolled up his trouser leg to exhibit his wounded knee. spread open show examine

It is absurd to predict that the sun will not rise tomorrow. ridiculous funny odd foolish

He is considered to be the most diligent student in class. kind-hearted hard-working short-sighted far-reaching

Play Play is the principal business of childhood, and in recent years research has shown the great importance of play in the development of a human being. From earliest infancy, every child needs opportunity and the right materials for play, and the main tools of play are toys. Their main function is to suggest, encourage and assist play. To succeed in this they must be good toys, which children will play with often, and will come back to again and again. Therefore it is important to choose suitable toys for different stages of a child’s development. In recent years research on infant development has shown that the standard a child is likely to reach, within the range of his inherited abilities, is largely determined in the first three years of his life. So a baby’s ability to profit from the right play materials should not be underestimated. A baby who is encouraged and stimulated, talked to and shown things and played with, has the best chance of growing up successfully. In the next stage, from three to five years old, curiosity knows no bounds. Every type of suitable toy should be made available to the child, for trying out, experimenting and learning, for discovering his own particular ability. Bricks and jigsaws (七巧板) and construction toys; painting, scribbling (涂鸦) and making things; sand and water play; toys for imaginative and pretending play; the first social games for learning to play and get on with others. By the third stage of play development -- from five to seven or eight years -- the child is at school. But for a few more years play is still the best way of learning, at home or at school. It is easier to see Which type of toys the child most enjoys. Until the age of seven or eight, play and work mean much the same to a child. But once reading has been mastered, then books and school become the main source of learning. Toys are still interesting and valuable, they lead on to new hobbies, but their significance has changed -- to a child of nine or ten years, toys. and games mean, as to adults, relaxation and fun.The passage tells us that as a child grows up he should be allowed to choose his own toys. he should be given identical toys. he should be given different toys. he should be given fewer and fewer toys.

My Life at Renda I learned very quickly that being a teaching assistant (TA) at the University of Iowa　would be different from being a teacher at Renmin University. 【46】______ Eyes staring, mouths open, students examined my big nose, while I was writing my name on the blackboard. At Iowa, when my first classes began, half of my students still hadn’t arrived. When everyone finally found a seat, ringing cellphones and loud yawns (哈欠) interrupted my opening remarks. It is not that American students were disrespectful. 【47】______ They were, however, far more skeptical than the students I had at Renda. The truth is I couldn’t fault them for their skepticism. Undergraduates at large US universities - especially freshmen and sophomores - often have several classes a semester handled by TAs. In some cases, the TA sets the course content. 【48】______ Most have good intentions, but very few are as effective as professors. Every teacher has to confront obstacles to learning - no matter what the culture. Students who talk during lectures, students who cheat, students who question the grade they get for a paper or project - dealing with these is all part of the job. 【49】______ The difference, I think, is that in the US I had to swallow more of my pride. 【50】______ I had a responsibility to teach them, of course, but I had to do so indirectly - as a guide who himself had a few things to learn from the students. A. In my students’ minds, I had little to offer them, except perhaps some sample questions for the mid-term exam. B. In others, the TA works as a grader and discussion leader. C. I encountered these in China, and I faced them in the US. D. On the other hand, being taught by a graduate student is not necessarily bad. E. Most were polite, or at least, indifferent F. Back at Renda, I had walked into my first classes feeling like a celebrity.

Customers often defer payment for as long as possible. make demand obtain postpone

The curious looks from the strangers around her made her feel uneasy. different proud unconscious uncomfortable

He is assigned to oversee the production of the assembly lines. supervise watch suspect predict

All living organisms, regardless of their unique identity, have certain logical, chemical, and physical characteristics in common. as a result of considering on purpose whatever

His strict upbringing inhibited him asking such stupid questions. instructed inquired forbad strived

The conclusion can be deduced from the premises. gone derived done come

Mary’s (perpetual) moaning nearly drove me mad. monotonous endless serious bitter

She persevered in her ideas despite obvious objections raised by friends. persisted insisted resisted suggested

The Food Scandal Widens As the scope of the food scandal widens in Taiwan—more than 200 firms and 500 products have been involved so far—some tainted commodities have been discovered in the mainland and the ripples of the DEHP(塑化剂) scare here call for a further response on the part of the authorities. The General Administration of Quality Supervision, Inspection and Quarantine has made the sensible decision to suspend the imports of Taiwan firms whose products have been confirmed as problematic. That was a necessary move, yet it is sufficient only to prevent a potential threat to public health from broadening further. At this point, the top priority for the safety authorities should be tracking down and recalling all the suspected beverages, snacks and perhaps raw materials from Taiwan. And it will do so, only if the quantity of problematic products in the mainland market is very, very small, as has been claimed by the companies themselves, and all of them are retractable. However, given the toxic nature of the plasticizer DEHP, its reportedly long existence in Taiwan’s food industry, as well as the latest report that the harmful substance was discovered in imported cosmetics, it might be more meaningful if the inspection extends beyond the designated items and product batches. Since some of the firms involved in the DEHP scandal have mainland subsidiaries, consumers need to know whether the food products they make and sell here are safe or not. Some of the firms involved have already claimed their mainland companies have independent suppliers, so their products on the mainland are free of DEHP. It would be wonderful if that is the truth. But that statement needs to be confirmed. And this is where our quality watchdogs should step in. Aside from worries about food products made in Taiwan, consumers here are wondering if DEHP, or any similar additive, has been used by local manufacturers. Since no inspection has been targeted specifically at DEHP, nobody can provide a definite answer. But considering the potentially high stakes, there has to be one. And we do not think it is a good idea for our authorities to wait until DEHP’s existence in food products becomes prevalent to launch a probe. Some speculations about the existence of DEHP in mainland food sectors might turn out to be groundless in the end. But because of its hazardous potential, even as a pre -emptive step, it is essential we act early.

Stanford University 1 Stanford University, famous as one of northern California’s several institutions of higher learning, is sometimes called “the Harvard of the West.“ The closeness of Stanford to San Francisco, a city thirty-two miles to the north, gives the university a decidedly cosmopolitan (世界性的) flavor. 2 The students are enrolled mainly from the western United States. But most of the fifty states send students to Stanford, and many foreign students study here, as well. And standards for admission remain high. Young men and women are selected to enter the university from the upper fifteen percent of their high school classes. 3 Not only because of the high caliber (素质) of its students but also because of the desirable location and climate, Stanford has attracted to its faculty some of the world’s most respected scholars. The university staff has included many Nobel prize winners such as Dr. Felix Bloch, Dr. Robert Hofstadter, and Dr. William Shockley in physics, Dr. Author Kornberg and Dr. Joshua Lederberg in medicine, and Dr. Paul J. Flory and Dr. Linus Pauling in chemistry. The Russian novelist Aleksandr Solzhenistsyn has been in residence. Stanford’s undergraduate school of engineering and its graduate schools of business, law, and medicine are especially well-regarded. 4 What is student life like on “The Farm“? Culturally, the campus is a magnet for both students and citizens of nearby communities. Plays, concerts, and operas are performed in the university’s several auditoriums and in its outdoor theater, where graduations are also held. Several film series are presented during the school year. Guest lecturers from public and academic life frequently appear on campus. In the evenings, many students gather to socialize in the Student Union’s coffee house; here the beverages (饮料) and the atmosphere both have a decidedly European flavor. For the sports-minded, the Stanford campus offers highly developed athletic facilities. Team sports, swimming, and track and field activity are all very much part or the Stanford picture. So are bicycling and jogging. 5 In addition to financial support from alumni (校友), Stanford receives grants from the government and from private philanthropic (慈善的) foundations. In recent years, government grants have made possible advanced studies in the fields of history, psychology,, education, and atomic energy. At present Stanford is carrying out an ambitious building program, financed in part by the Ford Foundation’s 25 million grant. Recently added to the campus are a new physics building, new school of business, new graduate school of law, new student union, and undergraduate library.A.Colorful Life on Campus B.Intelligent Student Body C.School Administration D.Distinguished Faculty E. Substantial Financial Support F. The Harvard of the West

Pretty Good When Spanish football club Barcelona paid US $ 35 million for Ronaldinho last summer, they weren’t buying a pretty face. “I am______(51),“ admits the Brazilian superstar (超级明星). “But everyone has got a different kind of beauty. What I_______(52) have is charm. “ Indeed he has. His buck teeth (龅牙) , flowing hair, big smile, and of course his_______(53) skills are always eye-catching on the pitch. The 23-year-old striker(中锋) scored two goals in a 3-2 win over Deportivo La Coruna on March 1. It was Barcelona’s sixth win in a row and, thanks to their Brazilian’s 10-goal contribution,_______(54)looked like a poor season could now end a success. Ronaldinho—full name Ronaldo De Assis Moreira—is one of many South Americans who learned their skills playing in the backstreets before_______(55) them off on the world stage. Great things were_______(56) when Gremio signed him as a seven-year-old, and he soon became friends with Ronaldo, who was then the other young star of Brazilian football. It was Ronaldo who first called him Ronaldinho, which_______(57) Little Ronaldo. He first_______(58) for his country in 1999 but it was at the 2002 World Cup where he showed his real worth, scoring an unbelievable free-kick in Brazil’s quarter-final victory_______(59) England. “I have never failed to deliver in big matches,“ Ronaldinho says. “ My game is based on improvisation (即兴表演). Often a forward does not have the time to decide whether to shoot or_______(60). It is instinct that gives out the orders.“ While he may not have David Beckham’s good looks, Ronaldinho has a_______(61) reputation off the pitch. At former club Paris Saint Germain, which sold him to Barcelona, he broke_______(62) rules by going out and enjoying the city’s nightlife. “Without doubt, Ronaldinho is the most_______(63) player I have ever come across,“ says former PSG coach Luis Ferdandez. “The main “_______(64)“ for any coach is that one player without discipline can hurt the “whole team.“ But Ronaldinho doesn’t think he has done anything wrong. “I am just a young person who enjoys____(65),“ he says. handsome good-looking ugly attractive

It’s prudent to take a thick coat in cold weather when you go out. controversial reasonable sensible sensitive

What can be inferred from the passage about the route to long life?

The average modified mouse lived

What does the last sentence in the third paragraph imply?

According to the passage, we do not know whether humans will benefit from taking in fewer calories partly because