阅读理解This passage is mainly about ______.

阅读理解Why does cream go bad faster than butter? Some researchers think they find the answer, and it comes down to the structure of the food, not its chemical composition—a finding that could help rid some processed foods of chemical preservatives. Cream and butter contain pretty much the same substances, so why cream should sour much faster has been a mystery. Both are emulsions—tiny globules (小球) of one liquid evenly distributed throughout another. "The difference lies in what''s in the globules and what''s in the surrounding liquid", says Brocklehurst, who led the investigation. In cream, fatty globules drift about in a sea of water. In butter, globules of a watery solution are locked away in a sea of fat. The bacteria which make the food go bad prefer to live in the watery regions of the mixture. "This means that in cream, the bacteria are free to grow throughout the mixture", he says. When the situation is reversed, the bacteria are locked away in compartments (密封舱) buried deep in the sea of fat. Trapped in this way, individual colonies cannot spread and rapidly run out of nutrients. They also slowly poison themselves with their waste products. "In butter, you get a self-limiting system which stops the bacteria growing", says Brocklehurst. The researchers are already working with food companies keen to see if their products can be made resistant to bacterial attack through alterations to the food''s structure. Brocklehurst believes it will be possible to make the emulsions used in salad cream, for instance, more like that in butter. The key will be to do this while keeping the salad cream liquid and not turning it into a solid lump.

阅读理解The view over a valley of a tiny village with thatched (草盖的) roof around a church; a drive through a narrow village street lined with thatched cottages painted pink or white; the sight over the rolling hills of a pretty collection of thatched farm buildings—these are still common sights in parts of England. Most people will agree that the thatched roof is an essential part of the attraction of the English countryside. Thatching is in fact the oldest of all the building crafts practiced in the British Isles (英伦诸岛). Although thatch has always been used for cottage and farm buildings, it was once used for castles and churches, too. Thatching is a solitary (独自的 ) craft, which often runs in families. The craft of thatching as it is practiced today has changed very little since the Middle Ages. Over 800 full-time thatchers are employed in England and Wales today, maintaining and renewing the old rods as well as thatching newer houses. Many property owners choose thatch not only for its beauty but became they know it will keep them cool in summer and warm in winter. In fact, if we look at developing countries, over half the world lives under thatch, but they all do it in different ways. People in developing countries are often reluctant to go back to traditional materials and would prefer modern buildings. However, they may lack the money to allow them to import the necessary materials. Their temporary mud huts with thatched roofs of wild grasses often only last six months. Thatch which has been done the British way lasts from twenty to sixty years, and is an effective defence against the heat.

阅读理解Elephants who paint aren''t new. Paintings by Ruby, an Asian elephant who lived at the Phoenix Zoo in Arizona, sold for up to $5,000 in the late 1980s, said Dick George, a consultant with the zoo. "Ruby was about seven months old when she first came to the zoo," said George. "She lived with a goat and some chickens, but she didn''t have an elephant companion for a number of years. She spent a lot of time drawing in the dirt with a stick to make her days more stimulating. Her keeper bought her some art supplies." George said, "Ruby was excited about painting right from the beginning." The elephants at the art academies in Southeast Asia are taught to hold a paintbrush with the tip of their trunks. Initially, the keeper guides the elephant''s trunk over the canvas (画布) and offers rewards for good performance. "It only takes a few hours to a day to teach them," said Mia Fine man, an art historian whose book "When Elephants Paint" is an illustrated history of the Asian Elephant Art and Conservation Project.

阅读理解Like many of my generation, I have a weakness for hero worship. At some point, however, we all to question our heroes and our need for them. This leads us to ask: What is a hero? Despite immense differences in cultures, heroes around the world generally share a number of characteristics that instruct and inspire people. A hero does something worth talking about. A hero has a story of adventure to tell and community who will listen. But a few heroes beyond mere fame. Heroes serve powers or principles larger than themselves. Like high-voltage transformers, heroes take the energy of higher powers and step it down so that it can be used by ordinary people. The hero lives a life worthy of imitation. Those who imitate a genuine, hero experience life with new depth, enthusiasm, and meaning. A sure test for would-be heroes is what or whom do they serve? What are they willing to live and die for? If the answer or evidence suggests they serve only their own fame, they may be famous persons but not heroes. Madonna and Michael Jackson are famous, but who would claim that their fans find life more abundant? Heroes are catalysts (催化剂) for change. They have a vision from the mountaintop. They have the skill and the charm to move the masses. They create new possibilities. Without Gandhi, India might still be part of the British Empire. Without Rosa Parks and Martin Luther King, Jr., we might still have segregated (隔离的) buses, restaurants, and parks: It may be possible for large scale change to occur without leaders with magnetic personalities, but the pace of change would be slow, the vision uncertain, and the committee meetings endless.

阅读理解How many different forms of communication are mentioned here?

阅读理解While still in its early stages, welfare reform has already been judged a great success in many states, at least in getting people off welfare. It''s estimated that more than 2 million people have left the rolls since 1994. In the past four years, welfare rolls in Athens County have been cut in half. But 70 percent of the people who left in the past two years took jobs that paid less than $6 an hour. The result: The Athens County poverty rate still remains at more than 30 percent—twice the national average. For advocates (代言人) for the poor, that''s an indication much more needs to be done. "More people are getting jobs, but it''s not making their lives any better," says Kathy Lairn, a policy analyst at the Center on Budget and Policy Priorities in Washington. A center analysis of US Census data nationwide found that between 1995 and 1996, a greater percentage of single, female-headed households were earning money on their own, but that average income for these households actually went down. But for many, the fact that poor people are able to support themselves almost as well without government aid as they did with it is in itself a huge victory. "Welfare was a poison. It was a toxin (毒素) that was poisoning the family," says Robert Rector, a welfare-reform policy analyst. "The reform is changing the moral climate in low-income communities. It''s beginning to rebuild the work ethic (道德观), which is much more important." Mr. Rector and others argued that once "the habit of dependency is cracked", then the country can make other policy changes aimed at improving living standards.

阅读理解Questions 26-30 are based on the following weather forecast: Weather Forecast The following forecast shows for the listed cities the projected weather conditions and the expected range of temperatures from the afternoon high to the evening low. Atlanta: Minneapolis: Mostly fair. 88—70°F. Mostly cloudy. 68—50°F. Boston: New Orleans: Partly cloudy. 78—61°F. Mostly fair. 92—73 °F. Chicago: Philadelphia: Thunderstorms likely. 82—67°F. Hazy and warm. 90—68°F. Cleveland: Phoenix: Mostly cloudy. 84—68°F. Sunny and warm. 99—66°F. Dallas: Pittsburgh: Thunderstorms likely. 91—75°F. Partly cloudy. 81—64°F. Denver: St. Louis: Rain likely. 53—43°F. Thunderstorms likely. 86—70°F. Houston: San Francisco: Partly cloudy. 90—78°F. Mostly fair. 73—60°F. Kansas City: Seattle: Thunderstorms likely. 73—63°F. Mostly fair. 74—50°F Las Vegas: Toronto: Sunny and warm. 93—56T. Rain likely. 83—68°F. Los Angeles: Washington: Mostly sunny. 88—60°F. Partly cloudy. 88—72°F. Miami: Partly cloudy. 88—79°F.

阅读理解Crossing Wesleyan University''s campus usually requires walking over colorful messages chalked on the ground. They can be as innocent as meeting announcements, but in a growing number of cases the language is meant to shock. It''s not uncommon, for instance, to see lewd references to professors'' sexual preferences scrawled across a path or the mention of the word "Nig" that African-American students say make them feel uncomfortable. In response, officials and students at schools are now debating ways to lead their communities away from forms of expression that offend or harass (侵扰). In the process, they''re putting up against the difficulties of regulating speech at institutions that pride themselves on fostering open debate. Mr. Bennet of Wesleyan says he had gotten used to seeing occasional chalkings filled with four-letter words. Campus tradition made any horizontal surface not attached to a building a potential billboard. But when chalkings began taking on a more threatening and lewd tone, Bennet decided to act. "This is not acceptable in a workplace and not acceptable in an institution of higher learning," Bennet says. For now, Bennet is seeking input about what kind of message-posting policy the school should adopt. The student assembly recently passed a resolution saying the "right to speech comes with implicit responsibilities to respect community standards." Other public universities have confronted problems this year while considering various ways of regulating where students can express themselves. At Harvard Law School, the recent controversy was more linked to the academic setting. Minority students there are seeking to curb what they consider harassing speech in the wake of a series of incidents last spring. At a meeting held by the "Committee on Healthy Diversity" last week, the school''s Black Law Students Association endorsed a policy targeting discriminatory harassment. It would trigger a review by school officials if there were charges of "severe or pervasive conduct" by students or faculty. The policy would cover harassment based on, but not limited to, factors such as race, religion, creed, sexual orientation, national origin, and ethnicity (种族划分). Boston attorney Harvey Silverglate, says other schools have adopted similar harassment policies that are actually speech codes, punishing students for raising certain ideas. "Restricting students from saying anything that would be perceived as very unpleasant by another student continues uninterrupted," says Silverglate, who attended the Harvard Law town meeting last week.

阅读理解One thing almost everyone is agreed on, including Americans, is that they place a very high valuation upon success. Success does not necessarily mean material rewards, but recognition of some sort—preferably measurable. If a boy turns out to be a preacher (传道者) instead of a businessman, that''s all right. But he bigger his church is, the more successful he is judged to be. A good many things contributed to this accent on success. There was the Puritan (清教徒的) belief in the virtue of work, both for its own sake and because the rewards it brought were regarded as signs of God''s love. There was the richness of opportunity in a land waiting to be settled. There was the lack of a settled society with fixed ranks and classes, so that a man was certain to rise through achievement. There was the determination of an immigrant to gain in the new world what had been denied to him in the old, and on the part of his children an urge to throw off the immigrant onus(负担) by still more success and still more rise in a fluid and classless society. Brothers did not compete within the family for the favor of the parents as in Europe, but worked hard for success in the outer world, along paths of their own choosing.

阅读理解The appeal of advertising to buying motives can have both negative and positive effects. Consumers may be convinced to buy a product of poor quality or high price because of an advertisement. For example, some advertisers have appealed to people''s desire for better fuel economy for their cars by advertising automotive products that improve gasoline mileage. Some of the products work. Others are worthless and a waste of consumers'' money. Sometimes advertising is intentionally misleading. A few years ago a brand of bread was offered to turned out that the bread was not dietetic (适合于节食的), but just regular bread: There were fewer calories because it was sliced very thin, but there were the same number of calories in every loaf. On the positive side, emotional appeals may respond to a consumer''s real concerns. Consider fire insurance. Fire insurance maybe sold by appealing to fear of loss. But fear of loss is the real reason for fire insurance. The security of knowing that property is protected by insurance makes the purchase of fire insurance a worthwhile investment for most people. If consumers consider the quality of the insurance plans as well as the message in the ads, they will benefit from the advertising. Each consumer must evaluate her or his own situation. Are the benefits of the product important enough to justify buying it? Advertising is intended to appeal to consumers, but it does not force them to buy the product. Consumers still control the final buying decision.

阅读理解Friction between America''s military and its civilian overseers is nothing new. America''s 220-year experiment in civilian control of the military is a recipe for friction. The nation''s history has seen a series of shifts in decision-making power among the White House, the civilian secretaries and the uniformed elite (精英). However, what may seem on the outside an unstable and special system of power sharing has, without a doubt, been a key to two centuries of military success. In the infighting dates to the revolution, George Washington waged a continual struggle not just for money, but to control the actual battle plan. The framers of the Constitution sought to clarify things by making the president the "commander in chief." Not since Washington wore his uniform and led the troops across the Alleghenies to quell (镇压) the Whiskey Rebellion has a sitting president taken command in the field. Yet the absolute authority of the president ensures his direct command. The president was boss, and everyone in uniform knew it. In the Civil War, Abraham Lincoln dealt directly with his generals, and Secretary of War Edwin M. Stanton handled administrative details. Lincoln, inexperienced in military matters, initially deferred (顺从) to his generals. But when their caution proved disastrous, he issued his General War Order No. 1—explicitly commanding a general advance of all Union forces. Some generals, George B. McClellan in particular, bridled at his hands-on direction. But in constitutional terms, Lincoln was in the right. His most important decision was to put Ulysses S. Grant in charge of the Union Army in 1864. Left to its own timetable, the military establishment would never have touched Grant. The relationship between the president and his general provides a textbook lesson in civilian control and power sharing. Grant was a general who would take the fight to the enemy, and not second-guess the president''s political decisions. Unlike McClellan, for example, Grant cooperated wholeheartedly in recruiting black soldiers. For his part, Lincoln did not meddle in operations and did not visit the headquarters in the field unless invited. The balance set up by Grant and Lincoln stayed more or less in place through World War I. Not until World War II did the pendulum finally swing back toward the White House. Franklin Roosevelt, who had been assistant Navy secretary during World War I, was as well prepared to be commander in chief as any wartime president since George Washington.

阅读理解How much do you have to pay for a coolest summer vacation?

阅读理解Which of the following statements about the real poet is NOT true?

阅读理解Violin prodigies (神童) , I learned, have come in distinct waves from distinct regions. Most of the great performers in the late 19th and early 20th centuries were born and brought up in Russia and Eastern Europe. I asked Isaac Stern, one of the world''s greatest violinists the reason for this phenomenon. "It is very clear," he told me. "They were all Jews (犹太人) and Jews at the time were severely oppressed and ill treated in that part of the world. They were not allowed into the professional fields, but they were allowed to achieve excellence on a concert stage." As a result, every Jewish parent''s dream was to have a child in the music school because it was a passport to the West. Another element in the emergence of prodigies, I found, is a society that values excellence in a certain field to nurture (培育) talent. Nowadays, the most nurturing societies seem to be in the Far East. "In Japan, a most competitive society, with stronger discipline than ours," says Isaac Stem, "children are ready to test their limits every day in many fields, including music. When Western music came to Japan after World War, that music not only became part of their daily lives, but it became a discipline as well. The Koreans and Chinese as we know, are just as highly motivated as the Japanese." That''s a good thing, because even prodigies must work hard. Next to hard work, biological inheritance plays an important role in the making of a prodigy. J. S. Bach, for example, was the top of several generations of musicians, and four of his sons had significant careers in music.

阅读理解While it is true that Americans believe climbing the educational ladder leads to success, they are less certain that intellectual achievement is the only important factor leading to success. A competitive personality is seen as important to success, especially in men. The development of social and political skills are also considered to be very important. To help Americans develop these other important skills, schools have added a large number of extracurricular (课程外) activities to daily life at school. This is especially true of high schools and colleges and extends down into elementary schools as well. Athletics, frequently called "competitive sports," are perhaps the most important of these activities. Football, basketball, and baseball teams are seen as very important in teaching students, particularly boys, the "winning spirit." At times, athletic teams seem to become more important to some students and their parents than the academic programs offered by the schools.

阅读理解Which of the following is probably the best title for the passage?

阅读理解Theme-park-bound bargain seekers would be wise to spend some time surfing online before they get in line at the parks this summer. A growing number of these attractions now allow customers to print e-tickets at home with large discounts off the gate price, in part to spur attendance that has declined in recent years. After boom times in the late 1990s, theme park attendance began to decrease, with an overall decline of about 4% over the past few years at North America''s 50 most-visited establishments, says James Zoltak, editor of Amusement Business. "The bloom was off the rose as we turned the corner into 2000, so there''s more discounting now," he says. Discounting isn''t new to an industry that has long partnered with other commercial enterprises, such as soft drink companies, to offer deals. But e-ticketing adds a new opportunity that not only brings savings but convenience as well, since it allows visitors to avoid the line at the gate. "If you can get in early before the lines fill up, you''re getting more for your money," says Robert Niles of the website Theme Park Insider.

阅读理解Whatis this passage mainly about?