A study by scientists in Finland has found that mobile phone radiation can cause changes in human cells that might affect the brain, the leader of the research team said. But Darius Leszczynski, who headed the 2-year study and will present findings next week at a conference in Quebec, said more research was needed to determine the seriousness of the changes and their impact on the brain or the body. The study at Finland"s Radiation and Nuclear Safety Authority found that exposure to radiation from mobile phones can cause increased activity in hundreds of proteins in human cells grown in a laboratory, he said. "We know that there is some biological response. We can detect it, with our very sensitive approaches, but we do not know whether it can have any physiological effects on the human brain or human body", Leszczynski said. Nonetheless the study, the initial findings of which were published last month in the scientific journal Differentiation, raises new questions about whether mobile phone radiation can weaker/the brain"s protective shield against harmful substances. The study focused on changes in cells that line blood vessels and on whether such changes could weaken the functioning of the blood-brain barrier, which prevents potentially harmful substances from entering the brain from the bloodstream, Leszczynski said. The study found that a protein called hsp27 linked to the functioning of the bloodbrain barrier showed increased activity due to irradiation and pointed to a possibility that such activity could make the shield more permeable, he said. "Increased protein activity might cause cells to shrink—not the blood vessels but the cells themselves—and then tiny gaps could appear between those cells through which some molecules could pass", he said. Leszczynski declined to speculate on what kind of health risks that could pose, but said a French study indicated that headache, fatigue and sleep disorders could result. "These are not life-threatening problems but can cause a lot of discomfort", he said, adding that a Swedish group had also suggested a possible link with Alzheimer"s disease. "Where the truth is I do not know", he said. Leszczynski said that he, his wife and children use mobile phones, and he said that he did not think his study suggested any need for new restrictions on mobile phone use.

For more than two decades, U.S. courts have been limiting affirmative-action programs in universities and other areas. The legal rationale is that racial preferences are unconstitutional, even those intended to compensate for racism or intolerance. For many colleges, this means students can be admitted only on merit, not on their race or ethnicity. It has been a divisive issue across the U. S., as educators blame the prolonged reaction to affirmative-action for declines in minority admissions. Meanwhile, activists continue to battle race preferences in courts from Michigan to North Carolina. Now chief executives of about two dozen companies have decided to plunge headfirst into this politically unsettled debate. They, together with 36 universities and 7 non-profitable organizations, formed a forum that set forth an action plan essentially designed to help colleges circumvent court-imposed restrictions on affirmative action. The CEOs" motive: "Our audience is growing more diverse, so the communities we serve benefit if our employees are racially and ethnically diverse" as well, says one CEO of a company that owns nine television stations. Among the steps the form is pushing: finding creative yet legal ways to boost minority enrollment through new admissions policies; promoting admissions decisions that look at more than test scores; and encouraging universities to step up their minority outreach and financial aid. And to counter accusations by critics to challenge these tactics in court, the group says it will give legal assistance to colleges sued for trying them. "Diversity diminished by the court must be made up for in other legitimate, legal ways", says a forum member. One of the more controversial methods advocated is the so-called 10% rule. The idea is for public universities—which educate three-quarters of all U. S. undergraduates—to admit students who are in the top 10% of their high school graduating class. Doing so allows colleges to take minorities who excel in average urban schools, even if they wouldn"t have made the cut under the current statewide ranking many universities use.

Teachers need to be aware of the emotional, intellectual, and physical changes that young adults experience. And they also need to give serious【B1】______to how they can best【B2】______such changes. Growing bodies need movement and【B3】______, but not just in ways that emphasize competition.【B4】______they are adjusting to their new bodies and a whole host of new intellectual and emotional challenges, teenagers are especially self-conscious and need the【B5】______that comes from achieving success and knowing that their accomplishments are【B6】______by others. However, the typical teenage lifestyle is already filled with so much competition that it would be【B7】______to plan activities in which there are more winners than losers,【B8】______, publishing newsletters with many student-written book reviews,【B9】______student artwork, and sponsoring book discussion clubs. A variety of small clubs can provide【B10】______opportunities for leadership, as well as for practice in successful【B11】______dynamics. Making friends is extremely important to teenagers, and many shy students need the【B12】______of some kind of organization with a supportive adult【B13】______visible in the background. In these activities, it is important to remember that the young teens have【B14】______attention spans. A variety of activities should be organized【B15】______participants can remain active as long as they want and then go on to【B16】______else without feeling guilty and without letting the other participants【B17】______. This does not mean that adults must accept irresponsibility.【B18】______, they can help students acquire a sense of commitment by【B19】______for roles that are within their【B20】______and their attention spans and by having clearly stated rules.

Addiction is such a harmful behavior, in fact, that evolution should have long ago weeded it out of the population: if it"s hard to drive safely under the influence, imagine trying to run from a saber-toothed tiger or catch a squirrel for lunch, And yet, says Dr. Nora Volkow, director of NIDA and a pioneer in the use of imaging to understand addiction, "the use of drugs has been recorded since the beginning of civilization. Humans in my view will always want to experiment with things to make them feel good". That"s because drugs of abuse co-opt the very brain functions that allowed our distant ancestors to survive in a hostile world. Our minds are programmed to pay extra attention to what neurologists call salience—that is, special relevance. Threats, for example, are highly salient, which is why we instinctively try to get away from them. But so are food and sex because they help the individual and the species survive. Drugs of abuse capitalize on this ready-made programming. When exposed to drugs, our memory systems, reward circuits, decision-making skills and conditioning kick in—salience in overdrive—to create an all consuming pattern of uncontrollable craving. "Some people have a genetic predisposition to addiction", says Volkow. "But because it involves these basic brain functions, everyone will become an addict if sufficiently exposed to drugs or alcohol". That can go for nonchemical addictions as well. Behaviors, from gambling to shopping to sex, may start out as habits but slide into addictions. Sometimes there might be a behavior-specific root of the problem. Volkow"s research group, for example, has shown that pathologically obese people who are compulsive eaters exhibit hyperactivity in the areas of the brain that process food stimuli—including the mouth, lips and tongue. For them, activating these regions is like opening the floodgates to the pleasure center. Almost anything deeply enjoyable can turn into an addiction, though. Of course, not everyone becomes an addict. That"s because we have other, more analytical regions that can evaluate consequences and override mere pleasure seeking. Brain imaging is showing exactly how that happens. Paulus, for example, looked at drug addicts enrolled in a VA hospital"s intensive four-week rehabilitation program. Those who were more likely to relapse in the first year after completing the program were also less able to complete tasks involving cognitive skills and less able to adjust to new rules quickly. This suggested that those patients might also be less adept at using analytical areas of the brain while performing decision-making tasks. Sure enough, brain scans showed that there were reduced levels of activation in the prefrontal cortex, where rational thought can override impulsive behavior. It"s impossible to say if the drugs might have damaged these abilities in the relapsers—an effect rather than a cause of the chemical abuse—but the fact that the cognitive deficit existed in only some of the drug users suggests that there was something innate that was unique to them. To his surprise, Paulus found that 80% to 90% of the time, he could accurately predict who would relapse within a year simply by examining the scans. Another area of focus for researchers involves the brain"s reward system, powered largely by the neurotransmitter dopamine. Investigators are looking specifically at the family of dopamine receptors that populate nerve cells and bind to the compound. The hope is that if you can reduce the effect of the brain chemical that carries the pleasurable signal, you can loosen the drug"s hold.

You are going to read a text about the situation of the blacks in America, followed by a list of examples and explanations. Choose the best example or explanation from the list for each numbered subheading. There is one extra example which you do not need to use. Although no longer slavers after the Civil War, American blacks took no significant part in the life of white America except as servants or laborers. Many thousands of them emigrated from the war-ravaged South to the North from 1865 to 1915 in the hope of finding work in the big industrial cities. Whole communities of blacks crowded together into ghettos in New York City, Chicago and Detroit, where once the poor white immigrants had lived. These ghettos, neglected by the city authorities, became slums. The schools to which black children went were hopelessly inadequate. Unemployment in black ghettos remained consistently higher than in white communities. (41) Serious problems with black ghettos. Stable family life was difficult to maintain. (42) The extreme poverty of the blacks. In the late 1970s, nearly a third of all blacks still belonged to the so-called "underclass", they are so "under-privileged" and poor that they cannot seize the opportunity for advancement. (43) Efforts to put an end to racial discrimination. Race relations in the USA continue to be a thorny problem, (44) Improvements in Ives of the blacks. Despite some setbacks, race relations are improving. (45) Prevailing violence in solving racial problems. It is said that television had an enormous influence on frustrated and hitter blacks, for it showed them bow much better whites on the whole lived than blacks. At the end of the 1960s, there were serious riots in many cities. The violence quickly died down. Blacks began to use their votes to exert political pressure. Cities like Atlanta (Georgia), Gary (Indiana), and Los Angeles (California) elected black mayors. Integration of schools, despite resistance from white groups, goes on, and the proportion of blacks in American colleges has increased dramatically in the last 20 years. There are reasons to maintain a cautious optimism that progress in race relations will continue.A. It has been estimated that there are more than 20 million Americans in this category, 10% of the population, including many millions of whites.B. Blacks are gaining in self-confidence. In more and more areas they are winning control of their communities, and their standard of living is going up faster than that of the poor whites. It is still a hard struggle. There is still prejudice and even some hatred, but in most walks of American life there are now more blacks than ever before.C. The era of blatant discrimination ended in the 1960s through the courageous actions of thousands of blacks participating in peaceful marches and sit-ins, to force Southern states to implement the Federal desegregation laws in schools and public accommodations. Down came the "whites only" notices in bused, hotels, trains, restaurants, sporting events, restrooms and on park benches that once could be found everywhere throughout the South. Gone were the restrictions that prevented blacks voting. Gone, too, were the hideous lynchings, which since the Civil War had caused the death of thousands of innocent blacks—hanged without trial by white mobs. However, even today, poor, uneducated lacks do not always receive the same degree of justice that the more affluent and better educated can expect.D. Many blacks chose to keep silent about their unfairness instead of resorting to violence. But their silence was also problem provoking: on the one hand, silence would build up a lot of complaints and hatred in their minds, thus resulting in a negative approach to life and everything; on the other hand, silence would give the whites an impression that the blacks take the reality for granted and put. more racial discrimination on them.E. Unemployed fathers would on occasion walk out of their homes and never return. Children neglected by their parents turned in some instances to drugs and crimes. There are more than 700 murders a year in cities like New York, Detroit, Los Angeles and Houston, and most of these deaths are of blacks killed by blacks. The black ghettos are dangerous both for blacks and non-blacks.F. Radical blacks like the Black panthers demanded a free black state within the Union, and advocated violence to achieve that end and to protect themselves against what they felt was police brutality toward blacks. For a while, violence overshadowed the influence of the greatly respected pacifist black, Martin Luther King, Jr., who had provided the inspiration and leadership for those devoted to a peaceful change and whose murder in 1968 stunned America.

Culture is the sum total of all the traditions, customs, belief and ways of life of a given group of human beings. In this sense, every group has a culture, however savage, undeveloped, or uncivilized it may seem to us. To the professional anthropologist, there is no intrinsic superiority of one culture over another, just as to the professional linguist there is no intrinsic hierarchy among languages. People once thought of the languages of backward groups as savage, undeveloped form of speech, consisting largely of grunts and groans. While it is possible that language in general began as a series of grunts and groans, it is a fact established by the study of "backward" languages that no spoken tongue answers that description today. Most languages of uncivilized groups are, by our most severe standards, extremely complex, delicate, and ingenious pieces of machinery for the transfer of ideas. They fall behind the western languages not in their sound patterns or grammatical structures, which usually are fully adequate for all language needs, but only in their vocabularies, which reflect the objects and activities known to their speakers. Even in this department, however, two things are to be noted: 1. All languages seem to possess the machinery for vocabulary expansion; either by putting together words already in existence or by borrowing them from other languages and adapting them to their own system. 2. The objects and activities requiring names and distinctions in "backward" languages, while different from ours; are often surprisingly numerous and complicated. A western language distinguishes merely between two degrees of remoteness ("this" and "that"); some languages of the American Indians distinguish between what is close to the speaker, or the person addressed, or remote from both, or out of sight, or in the past, or in the future. This study of language, in turn, casts a new light upon the claim of the anthropologists that all cultures are to viewed independently, and without ideas of rank or hierarchy.

You had a party at your home recently, but you unintentionally neglect to invite a close friend of yours, Victoria. Write a letter to1) make an apology, and2) explain how the mistake came about.Write your letter with no less than 100 words. Do not sign your name at the end of the letter. Use "Li Ming" instead. Do not write the address. (10 points)

A chemical plant should be responsible for the water pollution in a nearby river. Write a letter to the City Environment Protection Agency to 1) state the present situation, 2) suggest ways to deal with the problem and 3) express your sincere hope. You should write about 100 words. Do not sign your own name at the end of the letter. Use "Li Ming" instead. You do not need to write the address.

Real policemen, both Britain and the United States hardly recognize any resemblance between their lives and what they see on TV—if they ever get home in time. There are similarities, of course, but the cops don"t think much of them. The first difference is that a policeman"s real life revolves round the law. Most of his training is in criminal law. He has to know exactly what actions are crimes and what evidence can be used to prove them in court. He has to know nearly as much law as a professional lawyer, and what is more, he has to apply it on his feet, in the dark and rain, running down an alley after someone he has to talk to. Little of his time is spent in chatting to scantily clad ladies or in dramatic confrontations with desperate criminal. He will spend most of his working life typing millions of words on thousands of forms about hundreds of sad, unimportant people who are guilty—or not—of stupid, petty crimes. Most television crime drama is about finding the criminal; as soon as he"s arrested, the story is over. In real life, finding criminals is seldom much of a problem. Except in very serious cases like murders and terrorist attacks—where failure to produce results reflects on the standing of the police—little effort is spent on searching. The police have an elaborate machinery which eventually shows up most wanted men. Having made an arrest, a detective really starts to work. He has to prove his case in court and to do that he often has to gather a lot of different evidence. Much of this has to be given by people who don"t want to get involved in a court case. So as well as being overworked, a detective has to be out at all hours of the day and night interviewing his witnesses and persuading them, usually against their own best interests, to help him. A third big difference between the drama detective and the real one is the unpleasant moral twilight in which the real one lives. Detectives are subject to two opposing pressures: first as members of a police force they always have to behave with absolute legality, secondly, as expensive public servants they have to get results. They can hardly ever do both. Most of the time some of them have to break the rules in small ways. If the detective has to deceive the world, the world often deceives him. Hardly anyone he meets tells him the truth. And this separation the detective feels between himself and the rest of the world is deepened by the simple mindedness—as he sees it—of citizens, social workers, doctors, law makers, and judges, who, instead of stamping out crime punish the criminals less severely in the hope that this will make them reform. The result, detectives feel, is that nine tenths of their work is reaching people who should have stayed behind bars. This makes them rather cynical.

Studythefollowingpicturecarefullyandwriteanessayto1)describethepictureanddeduceitsmeaning,2)illustratetheproblemstheissuebringsabout,and3)suggestcountermeasures.Youshouldwrite160-200wordsneatly.

Most towns up to Elizabethan times were smaller than a modern village, and each of them was built a-round its weekly market where local produce was brought for sale and the town folks sold their work to the people from the countryside and provided them with refreshment for the day. Trade was virtually confined to that one day even in a town of a thousand or so people. On market days craftsmen put up their stalls in the open air whilst on one or two other days during the week the townsman would pack up his loaves, or nails, or cloth, and set out early to do a day"s trade in the market of an adjoining town where, however, he would be charged a heavy toll for the privilege and get a less favourable spot for his stand than the local craftsmen. Another chance for him to make a sale was to the congregation gathered for Sunday morning worship. Although no trade was allowed anywhere during the hours of the service (except at annual fair times), after church there would be some trade at the church door with departing country folk. The trade of markets was almost wholly concerned with exchanging the products of the nearby countryside and the goods sold in the market but particularly in food retail dealing was distrusted as a kind of profiteering. Even when there was enough trade being done to afford a livelihood to an enterprising man ready to buy wholesale and sell retail, town authorities were reluctant to allow it. Yet there were plainly people who were tempted to "forestall the market" by buying goods outside it, and to "regrate" them, that is to resell them, at a higher price. The constantly repeated rules against these practices and the endlessly recurring prosecutions mentioned in the records of all the larger towns prove that some well-informed and sharp-witted people did these things. Every town made its own laws and if it was big enough to have craft guilds, these associations would regulate the business of their members and tried to enforce a strict monopoly of their own trades. Yet while the guild leaders, as craftsmen, followed fiercely protectionist policies, at the same time, as leading townsmen, they wanted to see a big, busy market yielding a handsome revenue in various dues and tolls. Conflicts of interest led to endless, minute regulations, changeable, often inconsistent, frequently absurd. There was a time in the fourteenth century, for example, when London fishmongers were not allowed to handle any fish that had not already been exposed for sale for three days by the men who caught it.

Shopping has always been something of an impulse activity, in which objects that catch our fancy while strolling are immediately bought on a whim. Advertisers and sellers have taken advantage of this fact, carefully positioning inexpensive but attractive items on paths that we are most likely to cross, hoping that our human nature will lead to a greater profit for them. With the dawn of the Internet and its exploding use across the world, the same tactics apply. Advertisers now place "banners", links to commercial web sites decorated with attractive pictures designed to catch our eyes while browsing the webs, on key web sites with heavy traffic. They pay top dollar for the right, thus creating profits for the hosting web site as well. These actions are performed in the hopes that during the course of our casual and leisurely web surfing, we"ll click on that banner that sparks our interest and thus, in theory, buy the products advertised. Initial results have been positive. Web sites report a huge inflow of cash, both from the advertisers who tempt customers in with the banners and the hosting web sites, which are paid for allowing the banners to be put in place. As trust and confidence in Internet buying increases and information security is heightened with new technology, the volume of buying is increasing, leading to even greater profits. The current situation, however, is not quite as optimistic. Just as magazine readers tend to unconsciously ignore advertisements in their favorite periodicals, web browsers are beginning to allow banners to slip their notice as well. Internet users respond to the flood of banners by viewing them as annoyances, a negative image that is hurting sales, since users are now less reluctant to click on those banners, preferring not to support the system that puts them in place. If Internet advertising is to continue to be a viable and profitable business practice, new methods will need to be considered to reinvigorate the industry. With the recent depression in the technology sector and slowing economy, even new practices may not do the trick. As consumers are saving more and frequenting traditional real estate businesses over their Internet counterparts, the fate of Internet business is called into question. The coming years will be the only reliable indication of whether shopping on the World Wide Web is the wave of the future or simply an impulse activity whose whim has passed.Notes:on a whim 心血来潮。surf v.冲浪。in theory在理论上，顺理成章。hosting 访问率高的。call...into question 质疑，对…提出疑问。

"After a lifetime of being honest", says Collins, "all of a sudden I was basically being accused of stealing and treated like a criminal.

Suppose you are a librarian in your university. Write a notice of about 100 words, providing the newly-enrolled international students with relevant information about the library. You should write neatly on the ANSWER SHEET. Do not sign your own name at the end of die notice. Use " Li Ming" instead. Do not write the address. (10 points)

It has been justly said that while "we speak with our vocal organs we (1)_____ with our whole bodies," All of us communicate with one another (2)_____, as well as with words. Sometimes we know what we"re doing, as with the use of gestures such as the thumbs-up sign to indicate that we (3)_____ But most of the time we"re not aware that we"re doing it. We gesture with eyebrows or a hand, meet someone else"s eyes and (4)_____. These actions we (5)_____ are random and incidental. But researchers (6)_____ that there is a system of them almost as consistent and comprehensible as language, and they conclude that there is a whole (7)_____ of body language, (8)_____ the way we move, the gestures we employ, the posture we adopt, the facial expression we (9)_____, the extent to which we touch and the distance we stand (10)_____ each other. The body language serves a variety of purposes. Firstly it can replace verbal communication, (11)_____ with the use of gesture. Secondly it can modify verbal communication. Loudness and (12)_____ of voice is an example here. Thirdly "it regulates social interaction: turn taking is largely governed by non-verbal (13)_____. Finally it conveys our emotions and attitudes. This is (14)_____ important for successful cross-culture communication. Every culture has its own body language, and children absorb its nuances (15)_____ with spoken language. The way an Englishman crosses his legs is (16)_____ like the way a male American does it. When we communicate with people from other cultures, the body language sometimes help make the communication easy and (17)_____, such as shaking hand is such a (18)_____ gesture that people all over the world know that it is a signal for greeting. But sometimes the body language can cause certain misunderstanding (19)_____ people of different cultures often have different forms behavior for sending the same message or have different (20)_____ towards the same body signals.

In some early attempts by psychologists to describe the basic learning process, the terms "stimulus", "response" and "reinforcement" were introduced. In an educational setting, these (1)_____ could be defined as follows. When a teacher gives an (2)_____, or sets a problem, or asks a question, the pupil (3)_____ in some way, and the teacher then tells the pupil if he has responded correctly. The teacher"s first action is called the (4)_____. The pupil"s action, carrying out the instruction, or solving the problem, or answering the question, is (5)_____ the response. When the teacher tells the pupil his response is (6)_____, the bond between the stimulus and the response is strengthened and reinforcement is positive. If the response is incorrect, the bond is weakened, and reinforcement is (7)_____ Some psychologists laid great (8)_____ on the importance of reinforcement for continued learning. They (9)_____ that if a learner is not given information about his responses (feedback) he may not continue to respond. (10)_____, if his homework is not marked regularly, he will stop doing it. If in class, the answers he gives to the teacher"s questions are (11)_____ or brushed aside, he will stop trying to give any. Educational psychologists are, (12)_____, moving away from this simple, early (13)_____ of the basic learning process. The effects of feedback, for example, are seen to be more (14)_____ than this description suggests. Feedback does not merely positively or negatively (15)_____ the stimulus-response bond. It may (16)_____ confirm previously learned meanings and associations, correct mistakes, (17)_____ misunderstandings and show how well or badly different parts of the material have been learned. Thus (18)_____ may have the effect of increasing the learner"s confidence, backing up his previously (19)_____ knowledge, and showing him which items he has not (20)_____ grasped.

Athletes who cheat by injecting themselves with stored supplies of their own blood might soon be caught out. A revealing trail of debris could give the game away. Most "blood dopers" cheat by injecting themselves with the blood-boosting hormone erythropoietin(EPO), but there have been tests to detect EPO since 2000. Another way to dope blood is to periodically extract some of your own, store it and re-inject it before competitions. Some professional cyclists are alleged to have done this as part of a doping scandal that emerged in Spain in 2006, called Operacion Puerto. At least one cyclist is still fighting to clear his name. Re-injecting stored blood boosts the oxygen supply to muscles. The practice has so far eluded detection but now there might be a way catch out the cheats. During storage, red blood cells start to fall apart, generating debris such as the fragments of cell membranes(a cell membrane is the outside envelop of a living cell). Olaf Schumacher of the University of Freiburg in Germany and his colleagues have shown that when stored blood is re-injected, the recipient"s white blood cells prepare to get rid of this sudden tide of debris. They say that these changes on blood cell "debris" could betray sportsmen and make cheats detectable. "It"s like someone dumping rubbish in your blood," he says. "When all the rubbish comes at once, there"s lots of activity." Schumacher"s team took blood from six non-athletes, stored it for 35 days then re-infused it, taking further blood samples three and four days afterwards. When they analyzed the white blood cells in these samples, genes needed for identifying and disposing of ailing and damaged cells were much more active than usual. The gene changes led to the appearance of new proteins on the surface of the white blood cells which could potentially be picked up by antibodies, Schumacher says. He also suggests that antibodies could be created to detect the changes to the surface of red blood cells as well. Schumacher couldn"t say whether such tests would be ready in time for the 2012 Olympics in London. David Cowan, director of the UK Drug Control Centre at King"s College London, says: "The paper is promising, but more work is needed to establish a test that meets the rigorous standards required by sport so as not to falsely accuse an athlete." Schumacher says that one key goal is to make sure these changes only occur due to doping, rather than illness, for example.

TheImportanceofAbidingbyTrafficRulesWriteanessayof160-200wordsbasedonthedrawing.Inyouressay,youshould1)describethedrawingbriefly,2)explainitsintendedmeaning,and3)giveyourcomments.

The following paragraphs are given in a wrong order. For Questions 41-45, you are required to reorganize these paragraphs into a coherent article by choosing from the list A-G. Some of the paragraphs have been placed for you. (10 points)A. These issues cut right across traditional religious dogma. Many people cling to the belief that the origin of life required a unique divine act. But ff life on Earth is not unique, the case for a miraculous origin would be undermined. The discovery of even a humble bacterium on Mars, if it could be shown to have arisen independently from Earth life would support the view that life emerges naturally.B. Contrary to popular belief, speculation that we are not alone in the universe is as old as philosophy itself. The essential steps in the reasoning were based on the atomic theory of the ancient Greek philosopher Democritus. First, the laws of nature are universal. Second, there is nothing special or privileged about Earth. Finally, if something is possible, nature tends to make it happen. Philosophy is one thing, filling in the physical details is another. Although astronomers increasingly suspect that bio-friendly planets may be abundant in the universe, the chemical steps leading to life remain largely mysterious.C. There is, however, a contrary view-one that is gaining strength and directly challenges orthodox biology. It is that complexity can emerge spontaneously through a process of self-organization, ff matter and energy have an inbuilt tendency to amplify and channel organized complexity, the odds against the formation of life and the subsequent evolution of intelligence could be drastically shortened. The relevance of self-organization to biology remains hotly debated. It suggests, however, that although the universe as a whole may be dying, an opposite, progressive trend may also exist as a fundamental property of nature. The emergence of extraterrestrial life, particularly-intelligent life, is a key test for these rival paradigms.D. Similar reasoning applies to evolution. According to the orthodox view, Darwinian selection is utterly blind. Any impression that the transition from microbes to man represents progress is pure chauvinism of our part. The path of evolution is merely a random walk through the realm of possibilities. If this is right, there can be no directionality, no innate drive forward; in particular, no push toward consciousness and intelligence. Should Earth be struck by an asteroid, destroying all higher life-forms, intelligent beings, still less humanoids, would almost certainly not arise next time around.E. Traditionally, biologists believed that life is a freak-the result of a zillion-to-on& accidental concatenation of molecules. It follows that the likelihood of its happening again elsewhere in the cosmos is infinitesimal. This viewpoint de-rives from the second law of thermodynamics, which predicts that the universe is dying-slowly and inexorably degenerating toward a state of total chaos. Life stumbles across this trend only because it is a pure statistical luck.F. Historically, the Roman Catholic church regarded any discussion of alien life as heresy. Speculating about other inhabited worlds was one reason philosopher Giordano Bruno was burned at the stake in 1600. Belief that mankind has-a special relationship with God is central to the monotheistic religions. The existence of alien beings, especially if they were further advanced than humans intellectually and spiritually, would disrupt this cozy view.G. The discovery of life beyond earth would transform not only our science but also our religions, our belief systems and our entire world view. For in a sense, the search for extraterrestrial life is really a search for ourselves-who we are and what our place is in the grand sweep of the cosmos.Order: F is the first paragraph and G is the last.

The horse and carriage is thing of the past. But love and marriage are still with us and still closely interrelated. Most American marriages, particularly first marriages【B1】______young couples are the result of【B2】______attraction and affection【B3】______ than practical considerations. In the United States, parents do not arrange marriages for their children. Teenagers begin【B4】______in high school and usually find mates through their own academic and social【B5】______. Though young people feel【B6】______to choose their friends from【B7】______groups, most choose a mate of similar background. This is【B8】______in part to parental guidance. Parents cannot select spouses for their children, but they can usually【B9】______choices by【B10】______disapproval of someone they consider unsuitable. 【B11】______, marriages between members of different groups (interclass, interfaith, and interracial marriages) are increasing, probably because of the greater【B12】______of today's youth and the fact that they are restricted by【B13】______prejudices than their parents. Many young people leave their home towns to attend college,【B14】______in the armed forces,【B15】______pursue a career in a bigger city. Once away from home and family, they are more【B16】______to date and marry outside their own social group. In mobile American society, interclass marriages are neither【B17】______nor shocking. Interfaith marriages are【B18】______the rise particularly between Protestants and Catholics. On the other hand, interracial marriage is still very uncommon. It can be difficult for interracial couples to find a place to live, maintain friendships, and【B19】______a family. Marriages between people of different national【B20】______(but the same race and religion) have been commonplace here since colonial times.