The idea that some groups of people may be more intelligent than others is one of those hypotheses that dare not speak its name. But Gregory Cochran is【B1】______to say it anyway. He is that【B2】______bird, a scientist who works independently【B3】______any institution. He helped popularize the idea that some diseases not【B4】______thought to have a bacterial cause were actually infections, which aroused much controversy when it was first suggested. 【B5】______he, however, might tremble at the【B6】______of what he is about to do. Together with another two scientists, he is publishing a paper which not only【B7】______that one group of humanity is more intelligent than the others, but explains the process that has brought this about. The group in【B8】______are a particular people originated from central Europe. The process is natural selection. This group generally do well in IQ test,【B9】______12-15 points above the【B10】______value of 100, and have contributed【B11】______to the intellectual and cultural life of the West, as the【B12】______of their elites, including several world-renowned scientists,【B13】______. They also suffer more often than most people from a number of nasty genetic diseases, such as breast cancer. These facts,【B14】______, have previously been thought unrelated. The former has been【B15】______to social effects, such as a strong tradition of【B16】______education. The latter was seen as a(n)【B17】______of genetic isolation. Dr. Cochran suggests that the intelligence and diseases are intimately【B18】______. His argument is that the unusual history of these people has【B19】______them to unique evolutionary pressures that have resulted in this【B20】______state of affairs.

Many teachers believe that the responsibilities for learning lie with the student. (1)_____ a long reading assignment is given, instructors expect students to be familiar with the (2)_____ in the reading even if they do not discuss it in class or take an examination. The (3)_____ student is considered to be (4)_____ who is motivated to learn for the sake of (5)_____, not the one interested only in getting high grades. Sometimes homework is returned (6)_____ brief written comments but without a grade. Even if a grade is not given, the student is (7)_____ for learning the material assigned. When research is (8)_____,the professor expects the student to take it actively and to complete it with (9)_____ guidance. It is the (10)_____ responsibility to find books, magazines, and articles in the library. Professors do not have the time to explain (11)_____ a university library works; they expect students, (12)_____ graduate students, to be able to exhaust the reference (13)_____ in the library. Professor will help students who need it, but (14)_____ that their students should not be (15)_____,dependent on them. In the United States professors have many other duties (16)_____ teaching, such as administrative or research work. (17)_____, the time that a professor can spend with a student outside of class is (18)_____.If a student has problems with classroom work, the student should either, (19)_____ a professor during office hours (20)_____ make an appointment.

Do students learn from programmed instruction? The research leaves us in no doubt of this. They do, indeed, learn. (46) Many kinds of students learn—college, high school, secondary, primary, preschool, adult, professional, skilled labor, clerical employees, military, deaf, retarded imprisoned every kind of students that programs have been tried on. Using programs, these students are able to learn mathematics and science at different levels, foreign languages, English language correctness, spelling, electronics, computer science, psychology, statistics, business skills, reading skills, instrument flying rules, and many other subjects; the limits of the topics which can be studied efficiently by means of programs are not yet known. For each of the kinds of subject matter and the kinds of student mentioned above, experiments have demonstrated that a considerable amount of learning can be derived from programs; this learning has been measured either by comparing pre-and post-tests or the time and trials needed to reach a set criterion of performance. (47) But the question, how well do students learn from programs as compared to how well they learn from other kinds of instruction, we cannot answer quite confidently. Experimental psychologists typically do not take very seriously the evaluative experiments in which learning from programs is compared with learning from conventional teaching. Such experiments are doubtlessly useful, they say, for school administrators or teachers to prove to themselves (or their boards of education) that programs work. (48) But whereas one can describe fairly well the characteristics of a program, can one describe the characteristics of a classroom teaching situation so that the result of the comparison will have any generality? What kind of teacher is being compared to what kind of program? Furthermore, these early evaluative experiments with programs are likely to suffer from the Hawthorne effect; that is to say, students are in the spotlight when testing something new, and are challenged to do well. (49) It is very hard to make allowance for this effect; therefore, the evaluative tests may be useful administratively, say many of the experiments, but do not contribute much to science, and should properly be kept for private use. These objections are well taken. And yet, do they justify us in ignoring the evaluative studies? The great strength of a program is that it permits the student to learn efficiently by himself. (50) Is it not therefore important to know how much and what kind of skills, concepts, insights, or attitudes he can learn by himself from a program as compared to what he can learn from a teacher? Admittedly, this is a very difficult and complex research problem, but that should not keep us from trying to solve it.

Until now, it had been widely assumed that the kind of mental ability that allows us to solve new problems without having any relevant previous experience—what psychologists call fluid intelligence—is innate and cannot be taught(though people can raise their grades on tests of it by practicing). But in a new study, researchers describe a method for improving this skill, along with experiments to prove it works. The key, researchers found, was carefully structured training in working memory—the kind that allows memorization of a telephone number just long enough to dial it. This type of memory is closely related to fluid intelligence, according to background information in the article, and appears to rely on the same brain circuitry. So the researchers reasoned that improving it might lead to improvements in fluid intelligence. First they measured the fluid intelligence of four groups of volunteers using standard tests. Then they trained each in a complicated memory task, the child" s card game, in which they memorized simultaneously presented auditory and visual stimuli that they had to recall later. The game was set up so that as the participants succeeded, the tasks became harder, and as they failed, the tasks became easier. This assured a high level of difficulty, adjusted individually for each participant, but not so high as to destroy motivation to keep working. The four groups underwent a half-hour of training daily for 8, 12, 17 and 19 days, respectively. At the end of each training, researchers tested the participants" fluid intelligence again. To make sure they were not just improving their test-taking skills, the researchers compared them with control groups that took the tests without the training. The results, published Monday in The Proceedings of the National Academy of Sciences, were striking. Although the control groups also made gains, presumably because they had practice with the fluid intelligence tests, improvement in the trained groups was substantially greater. Moreover, the longer they trained, the higher their scores were. All performers, from the weakest to the strongest, showed significant improvement. "Intelligence has always been considered principally an immutable inherited trait," said Susanne M. Jaeggi, a postdoctoral fellow in psychology at the University of Michigan and a co-author of the paper. "Our results show you can increase your intelligence with appropriate training. " Why did the training work? The authors suggest several aspects of the exercise relevant to solving new problems: ignoring irrelevant items, monitoring ongoing performance, managing two tasks simultaneously and connecting related items to one another in space and time.

The key position and role of women in the process of development is increasingly being recognized. (1)_____ the three great World Conferences of Women were more concerned (2)_____ recognizing and compiling approaches to (3)_____, we can currently confirm a general sharpening of awareness. It has become clear that the Third World Cultures, in earlier times strongly matriarchal, have been weakened (4)_____ this respect by the methods of colonial education which are almost (5)_____ directed towards the male. Of the many criticisms of this situation let one voice be heard: "Development education groups and programmes are very much (6)_____ and lack woman"s perspective". So, too, the hopes placed in vocational training—"vocationalization"—as an aid to equality have been disappointed since this in its turn was to large extent focused on the male. In these circumstances we should not be surprised that until now women have (7)_____ at least in the educational processes which have been introduced. Only 20% attend primary school and the (8)_____ of those who leave early is highest (9)_____ girls. Because of the lack of basic training only around 10% take part in Adult Education programmes. Hence it is vitally important to (10)_____ a turning-point by increasing the (11)_____ of the need (12)_____ education. Hence even Primary Education for girls should be (13)_____ towards the basic needs and necessities and provide answers which are as simple as possible. In rural districts such answers will be different from those (14)_____ in urban areas. The education of girls and women must to a large degree be an education for the life they will lead, tailored (15)_____ a woman"s position. In saying this we are in fact demanding that the education of women, like all educational work in the Third World, should be an (16)_____ part of the community. (17)_____ there are many partners in this process school, family, small businesses, governmental and non-governmental organizations. The educational skill (18)_____ keeping this interplay active in such a way that there is no deficiency in material content. An important consequence of this is the (19)_____ of the desire to question, which, on the one hand, presses for further education and on the other for its (20)_____ application.

(46) As technology continues to advance, countries must decide how they will deal with the issue of human cloning for reproduction or research. So far, several nations have placed strong restrictions on healing cloning; others are moving towards such restrictions, and a few have staked out positions in favor of curative cloning. After months of bitter debate, the Unite States must decide what it will do. All legislators can agree that it would be wrong now to make a walking, talking, real-life human clone. The National Academy of Sciences also supports that position. But its institute of Medicine has rightly said that its objections to the safety of reproductive cloning do not apply to research cloning. Indeed," some scientists say that research cloning could yield stem cells that could be used to grow healing tissues for patients with diseases such as Parkinson"s. (47) They also say that studying stem cells made from the cells of diseased patients could help us understand why people with the same genetic make-up get sick or stay well. Opponents of research cloning say there is no proof that it will yield any cures. They also say that adult stem cells are more promising and less controversial. They have gained Congressional and public support by beating into widespread fears about biotechnology, which some worry is winding quickly down a slippery slope towards the commodification of the human species. (48) But such fears do not represent a sensible basis for a ban on research cloning, which is likely to give insights into the processes that cause a host of devastating diseases. The Senate is now moving towards a slowdown on the issue. Two bills have been introduced. Senator Sam Brownback introduced a bill that would ban cloning for any purpose. His rivals, led by Senator Dianne Feinstein, have introduced competing legislation that would all low scientists to close embryos for research. And senators eager to air their views on the issue for a vote on the matter in the next few weeks. (49) Brown back is said to have nearly 50 supporters, but for technical reasons a bill is unlikely to be passed unless 60 senators support it. Advocates of healing cloning have outlined situations that would make the Senate more likely to pass a bill that would allow research cloning, such as amending the Brownback bill to allow research. In this way, senators could save face by simultaneously voting for Brownback and for research. However, any bill that does pass the Senate must be reconciled with the House bill in a conference, The Brownback bill is virtually identical to a House cloning ban that was passed last July. So it would speed through the conference committee. But Senate and House negotiators are unlikely to compromise if the Senate votes to allow healing cloning, (50) So the result of this month"s Senate debate is likely to be either that President Bush signs a bill that bans cloning for any purpose, or that he does not sign any cloning bill at all. The issue could also spill over into the appropriations process this autumn, when senators try to force rules through the Congress by attaching them to the necessary spending bills. The Congress has strongly supported the National Institute of Health in recent years because it wants the United States to be a world leader in biomedical research. The Senate should continue its strong support of biomedical science, and act in the national interest, by refusing to pass a ban on research cloning.

What Will Money Bring Us, Fortune or Misfortune?

During the traditional wedding ceremony, the【C1】______couple promise each other lifelong devotion. Yet, about one out of four American marriages ends in divorce. Since 1940, the divorce rate has more than doubled, and experts predict that, of all marriages that【C2】______in the 2000s, about 50% will end in divorce. The U.S. has one of the highest divorce rates in the world, perhaps【C3】______the highest. What goes wrong? The fact that divorce is so【C4】______in the United States does not mean that Americans consider marriage a casual, unimportant【C5】______. Just the opposite is【C6】______. Americans expect a great【C7】______from marriage. They seek physical, emotional, and intellectual compatibility. They want to be deeply loved and【C8】______. It is because Americans expect so much from marriage that so many get divorced. They prefer no marriage at all to a marriage without love and understanding. With typical American optimism, they end one marriage【C9】______that the next will be happier.【C10】______no-fault divorce laws in many states, it is easier than before to get a divorce. Some American women,【C11】______in unhappy marriages because they don"t have the education or job【C12】______to support themselves and their children. But most American women believe that, if【C13】______, they can make it alone without a husband. When a couple gets divorced, the court may【C14】______the man to pay his former wife a monthly sum of money called alimony. The amount of alimony【C15】______on the husband"s income, the wife"s needs and the【C16】______of the marriage. 【C17】______, the court decides that a woman should pay her husband alimony. About 10% of American women【C18】______their husbands. The court may decide that she must continue to【C19】______him after the divorce. This is a rather new【C20】______in the United States.

Washington, DC has traditionally been an unbalanced city when it comes to the life of the mind. It has great national monuments, from the Smithsonian museums to the Library of Congress. But day-to-day cultural life can be thin. It attracts some of the country"s best brains. But far too much of the city"s intellectual life is devoted to the minutiae of the political process. Dinner table conversation can all too easily turn to budget reconciliation or social security. This is changing. On October 1st the Shakespeare Theatre Company opened a 775-seat new theatre in the heart of downtown. Sidney Harman hall not only provides a new stage for a theatre company that has hitherto had to make do with the 450-seat Lansburgh Theatre around the corner. It will also provide a platform for many smaller arts companies. The fact that so many of these outfits are queuing up to perform is testimony to Washington"s cultural vitality. The recently-expanded Kennedy Centre is by some measures the busiest performing arts complex. But it still has a growing number of arts groups which are desperate for mid-sized space down-town. Michael Kahn, the theatre company"s artistic director, jokes that, despite Washington"s aversion(厌恶) to keeping secrets, it has made a pretty good job of keeping quiet about its artistic life. The Harman Centre should act as a whistle blower. Washington still bows the knee to New York and Chicago when it comes to culture. But it has a good claim to be America"s intellectual capital. It has the greatest collection of think-tanks on the planet, and it regularly sucks in a giant share of the country"s best brains. Washington is second only to San Francisco for the proportion of residents twenty-five years and older with a bachelor"s degree or higher. Washington"s intellectual life has been supercharged during the Bush years, despite the Decider"s aversion to ideas. September 11th, 2001, put questions of global strategy at the center of the national debate. Most of America"s intellectual centers are firmly in the grip of the left-liberal establishment. For all their talk of "diversity" American universities are allergic to a diversity of ideas. Washington is one of the few cities where conservatives regularly do battle with liberals. It is also the center of a fierce debate about the future direction of conservatism. The danger for Washington is that this intellectual and cultural renaissance will leave the majority of the citizens untouched. The capital remains a city deeply divided between over-educated white itinerants and under- educated black locals. Still, the new Shakespeare theatre is part of job-generating downtown revival. Twenty years ago downtown was a desert of dilapidated(破旧的) buildings and bag people. Today it is bustling with life. If Washington is struggling to fix the world, at least it is making a reasonable job of fixing itself.

Across the developed world, health-care spending is rising and will continue to in crease as populations age. As each country feels the financial strain, it is tempting to imagine that there must be a better way of funding medical care elsewhere. In Britain, for example, Bernard Ribeiro, the new president of the Royal College of Surgeons, has called for the National Health Service (NHS) to be financed from social-insurance contributions, as in Germany and France, rather than from general taxation. He worries that a tax-financed system will not deliver enough resources to meet the demand for health-care spending in the longer run. There are indeed good reasons for concern about the way the NHS is financed, for it has allowed the government to pump in too much money too fast. But there is no ideal sys tem for paying for health care. The European social-insurance model is in even more trouble than Britain"s tax-based model. By loading the burden on to employers and workers and thus raising labour costs, it has contributed to the inflexibility of labour markets and thus to the Euro-sclerosis that continental governments are struggling to recover from. In France, the government has resorted to general taxation to spread the burden. In Germany and elsewhere the model looks increasingly unsustainable, not least because its narrow fiscal base will be exposed to unfavourable demographics when the post-war baby-boomers start leaving the labour force in droves. Nor does America offer an ideal solution. It has a mixed financing system, in which the government stumps up for the elderly and the poor, and employers pay for private coverage of their workers. Health-care spending has reached a record 15% of GDP, dwarfing Britain"s 8%, yet 45m Americans lack insurance cover. The rising cost of publicly-financed medical care threatens America"s fiscal health. Rather than focusing on how the money is raised, reformers should worry about how it is spent. Health-care expenditure is rocketing not just because demand is rising but also because health-care markets work badly. They are dominated by powerful providers—companies, hospitals and influential doctors—which find it fairly easy to pass on ever-rising costs from new medical technologies to the state or the insurers who pick up most of the tab. Private individuals" payments generally account for a smallish share of health care spending precisely because medical bills tend to be so high that everybody needs insurance cover of one sort or another. Taxes, social-insurance contributions and payments by employers all boil down to forms of health insurance. The cure is not to try to raise yet more money in a different way. Instead, the overriding goal must be to spend the money pouring into health care more effectively by getting wasteful medical systems to work better. Two sets of reform are vital and both, as it hap pens, are being undertaken in Britain"s tax-financed NHS.

All Sumerian cities recognized a number of gods in common, including the sky god, the lord of storms, and the morning and evening star. 【B1】______ the Sumerian worshipped the goddess of fertility, love, and war, she was evidently lower 【B2】______ status than the male gods, indicating that in a more urbanized society the【B3】______that the peoples of previous times had paid to the earth mother goddess had【B4】______. The gods seemed hopelessly violent and【B5】______, and one' s life a period of slavery at their easy will. The epic poem The Creation emphasizes that【B6】______were created to enable the gods to 【B7】______ up working. Each city moreover had its own god, who was considered to【B8】______the temple literally and who was in theory the owner of all property within the city. 【B9】______the priests who interpreted the will of the god and controlled the【B10】______of the economic produce of the city were favored【B11】______their supernatural and material functions【B12】______. When, after 3,000 B. C., growing warfare among the cities made military leadership【B13】______, the head of the army who became king assumed a (a) 【B14】______ position between the god, whose agent he was, and the priestly class, whom he had both to use and to【B15】______. Thus king and priests represented the upper class in a hierarchical society.【B16】______them were the scribes, the secular attendants of the temple, who【B17】______every aspect of the city's economic life and who developed a rough judicial system.【B18】______the temple officials, society was divided among an elite or【B19】______group of large landowners and military leaders; a mixed group of merchants, artisans, and craftsmen, free peasants who【B20】______the majority of the population; and slaves.

BSection I Use of EnglishDirections: Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D./B

Nothing has come to embody corporate greed like executive perks: the corporate jets, chauffeured limousines and country-club memberships that bosses consume in a seemingly deliberate attempt to outrage public opinion. Not for nothing bas Warren Buffett. Omaha"s celebrated investor, named his corporate jet "The Indefensible". The usual explanation for the perk is that it is a (rather enjoyable) way for corporate insiders to misappropriate shareholders" money. (46) Because perks are poorly disclosed shareholders have no way of knowing when the boss is living it up at their expense. This has led to the theory that perk-laden executives are likeliest to be found in firms with lots of cash, but few investment prospects. But in a recent paper, Raghuram Rajah, the IMF"s chief economist, and Julie Wulf, of the Wharton School, looked at how more than 300 big companies dished out perks to their executives in 1986-99. (47) It turns out that neither cash-rich, low-growth firms nor firms with weak governance shower their executives with unusually generous perks. The authors did, however, find evidence to support two competing explanations. (48) First firms in the sample with more hierarchical organisations lavished more perks on their executives than firms with flatter structures. Why? Perks are a cheap way to demonstrate stares. Just as the armed forces ration medals, firms ration the distribution of conspicuous symbols of corporate status. Second, perks are a cheap way to boost executive productivity. (49) Firms based in places where it takes a long time to commute are more likely to give the boss a chauffeured limousine. Firms located far from large airports are likelier to lay on a corporate jet. So there it is. The boss needs his luxury pad on Fifth Avenue and his chauffeured stretch-limo because he might otherwise do less work. (50) Making it harder for the boss to consume conspicuously risks dangerous anarchy as, bereft of its symbols of corporate status, the firm"s hierarchy collapses into a muddled heap. Perhaps, in light of these findings, Mr. Buffett should call his next jet "The Indispensable".

Public health officials grappling with the obesity epidemic have debated a wide range of approaches to helping slim the American waistline. To some degree, everything from building more sidewalks to banning chocolate milk has been explored. Yet few tactics have been as polarizing as the possibility of introducing tariffs on treats. Despite endorsement from several respected obesity re-searchers and politicians, soda taxes, for example, have been subject to severe scrutiny, as critics protested that implementing a tax before verifying that it would achieve the end result was shortsighted and potentially overreaching. So, in attempt to determine just how sin taxes might impact people"s food choices, psychologists from the University of Buffalo decided to put junk food levies to the test—in the lab. Researchers recruited shoppers to examine the aisles of a mock supermarket filled with 68 common foods labeled with nutritional information. Participants were given a predetermined amount of cash, and were told to use that money to purchase a week"s worth of groceries for a family. The first time, all of the products on the shelves were priced in keeping with local supermarkets. In subsequent trips, however, junk food was taxed—an additional 12.5%, then 25%—or healthier foods were subsidized to reduce cost. The study, published in the journal Psychological Science, revealed that taxes were more effective at getting people to avoid certain products than subsidies were at prompting healthier food purchases. In scenarios where junk foods were taxed, study participants generally came away with a lower caloric total for their groceries, and a higher ratio of protein to fats and carbohydrates. Yet, in situations where healthy foods were subsidized, the savings were often spent on additional junk food. That is, instead of stocking up on more fruits and vegetables because they were cheaper, the study"s shoppers bought their vegetables, and then used the leftover cash to bring home extra treats like chips and soda. In the end, the subsidies—only scenarios resulted in higher total calorie counts, and didn"t result in overall nutritional improvement on the week"s groceries. Because the scenario is hypothetical, the findings certainly shouldn"t be taken as the final word in the sin tax debate, the researchers stress, but should instead be used to inform the ongoing discussion about practical ways to battle obesity. To that end, they say, the next step should be research to determine whether these results would be replicated in the real world.

You have just spent a weekend staying at the Lilo Hotel in Adelaide. When you got home you found that you had left a bag at the hotel. Write to the manager of the hotel: 1) giving any relevant information about the bag and its contents, 2) asking the manager to contact you immediately if the bag is found and 3) telling him/her how the bag can be sent to you. You should write about 100 words on the ANSWER SHEET. Do not sign your own name at the end of the letter. Use "Li Ming" instead. Do not write the address. (10 points)

BSection II Reading Comprehension/B

In the early 1800s, groups of English workers wrecked machines that they felt threatened their jobs. (46) They were called "Luddites" after one of their leaders, a term that is now used for anyone who puts up resistance to new technologies. (47) The odd thing about nanotechnology"s Luddites is that they have started resisting before the technology has really established itself. As people start to buy products involving nanotechnology, from odour-resistant shirts to window glass that repels dirt, they will realise that many of these new things are useful and harmless. And as awareness of nanotechnology grows, they will begin to understand that it covers a range of different ways of doing things, some of which carry some risk and others do not. As a result, the technology"s detractors will probably become more nuanced in their complaints. Nanotechnology has the potential to cause an industrial upheaval, just as electricity did in its time. (48) Like electricity, though, it has so many and such diverse applications that it is unlikely to arrive in one huge wave, as nanotechnology"s critics fear. In stead, there will be a series of smaller waves. (49) Many of the innovations the technology may bring are a long way off, leaving plenty of time to prepare. Nanotechnology, like any new discovery, offers both risks and rewards. There will undoubtedly be some need to control its exploitation to minimize the risks, but there are also strong arguments for allowing the unfettered pursuit of knowledge: without it, innovation cannot flourish. Twenty years ago, nobody could have foreseen that the invention of a new microscope would launch a remarkable new technology, perhaps a revolution. (50) Scientists should be allowed to work with as little hindrance as possible to gain a better understanding of the object of their study—however large or small.

The homeless make up a growing percentage of America' s population.【B1】______, homelessness has reached such proportions that local governments can't possibly【B2】______. To help homeless people【B3】______independence, the federal government must support job training programs,【B4】______the minimum wage, and fund more low-cost housing. 【B5】______everyone agrees on the number of Americans who are homeless. Estimates【B6】______anywhere from 600, 000 to 3 million.【B7】______the figure may vary, analysts do agree on another matter: that the number of the homeless is【B8】______. One of the federal government's studies【B9】______that the number of the homeless will reach nearly 19 million by the end of this decade. Finding ways to【B10】______this growing homeless population has become increasingly difficult.【B11】______when homeless individuals manage to find a【B12】______that will give them three meals a day and a place to sleep at night, a good number still spend the bulk of each day【B13】______the street. Part of the problem is that many homeless adults are addicted to alcohol or drugs. And a significant number of the homeless have serious mental disorders. Many others,【B14】______not addicted or mentally ill, simply lack the everyday【B15】______skills needed to turn their lives【B16】______. Boston Globe reporter Chris Reidy notes that the situation will improve only when there are【B17】______programs that address the many needs of the homeless. 【B18】______Edward Zlotkowski, director of community service at Bentley College in Massachusetts,【B19】______it, "There has to be【B20】______of programs. What's needed is a package deal."

【F1】 To explain why some countries grow more rapidly than others or why a country may grow more rapidly during one period of history than another, economists have found it convenient to think in terms of a "production function". This is a mathematical way of relating some measure of output, such as GNP, to the inputs required to produce it. For example, it is possible to relate GNP to the size of the labour force measured in man-hours, to capital stock measured in dollars, and to various other inputs that are considered important. An equation can be written that states that the rate of growth of GNP depends upon the rates of growth of the labour force, the capital stock, and other variables.【F2】 A common procedure is to assume that the influence of the separate inputs is additive—i. e. , that the increase in the growth of output caused by increasing the rate of growth of, say, capital is independent of the rate of growth of the labour force. This is the starting point of a great deal of current empirical work that attempts to quantify the importance of different inputs. 【F3】 Under certain assumptions, some reasonable and some patently false, it is possible to conclude that what labour and capital receive in the form of wages, profits, and interest is a fair measure of what they contribute to the productive process. Thus in the United States in the period following World War II the share of output going to labour was approximately 79 percent, while the share of output distributed as "profits" was 21 percent.【F4】 If we assume that these proportions determine how much we should weight the rate of growth of the labour force and of capital respectively in determining their contribution to the rate of growth of output, we must conclude that the relative contribution of capital is slight. 【F5】 Alternatively,we may say that some given percentage increase in the rate of growth of the labour force will have a much larger influence on the rate of growth of output than the same percentage increase in the rate of growth of capital. This is a puzzling result and can be traced to the assumption that the influence of separate inputs is additive.

Title: MY HOMETOWNWord limit: 160 - 200 wordsTime limit: 40 minutesYou are required to develop your essay according to the given topic sentence of each paragraph.1. My hometown is very beautiful.2. Some changes of my hometown.3. The people of my hometown.