问答题In the span of 18 months, Isaac Newton invented calculus, constructed a theory of optics, explained how gravity works and discovered his laws of motion. As a result, 1665 and the early months of 1666 are termed his annus mirabilis. (46) It was a sustained sprint of intellectual achievement that no one thought could ever be equaled. But in a span of a few years just before 1900, it all began to unravel. One phenomenon after another was discovered which could not be explained by the laws of classical physics. (47) The theories of Newton, and of James Clerk Maxwell who followed him in the mid-19th century by crafting a more comprehensive account of electromagnetism, were in trouble. Then, in i905, a young patent clerk named Albert Einstein found the way forward. In five remarkable papers, he showed that atoms are real (it was still controversial at the time), presented his special theory of relativity, and put quantum theory on its feet. It was a different achievement from Newton's year, but Einstein's annus mirabilis was no less remarkable. He did not, like Newton, have to invent entirely new forms of mathematics. However, he had to revise notions of space and time fundamentally. (48) And unlike Newton, who did not publish his results for nearly 20 years, so obsessed was he with secrecy and working out the details, Einstein released his papers one after another, as a fusillade of ideas. For Einstein, it was just a beginning--he would go on to create the general theory of relativity and to pioneer quantum mechanics. While Newton came up with one system for explaining the World, Einstein thus came up with two. Unfortunately, his discoveries--relativity and quantum theory--contradict one another. Both cannot be true everywhere, although both are remarkably accurate in their respective domains of the very large and the very small. Einstein would spend the last years of his life attempting to reconcile the two theories, and failing. (49) But then, no one else has succeeded in fixing the problems either, and Einstein was perhaps the one who saw them most clearly. When Einstein was awarded a Nobel prize, in 1921, it was for the first of his papers of 1905, which proved the existence of photons--particles of light. (50) Up until that paper, completed on March 17th and published in Annalen der Physik (as were the other 1905 papers), light had been supposed to be a wave, since this explains the interference patterns created when it passes through a grating. Einstein, however, began from a different premise, by considering the so-called "black-body experiment".

问答题Directions:Writeanessayofabout160-200wordsbasedonthefollowingdrawing.Inthisessay,youshould:1)describethepicturesbriefly,2)interpretthemeaning,and3)giveyourcomment.YoushouldwriteneatlyonANSWERSHEET2.

问答题Directions: Recently you were a visitor wanting to exit a gallery and you were confronted with misleading signs that read rather awkwardly, "Way Out" or "Export". Write a letter to the department concerned, politely suggesting they rectify the mistranslations. You should elaborate an effective way to deal with this problem. Write your letter in no less than 100 words. Write it neatly on ANSWER SHEET 2. Do not sign your own name at the end of the letter, use "Li Ming" instead. Do not write the address.

问答题As civilization proceeds in the direction of technology, it passes the point of supplying ai1 the basic essentials of life--food, shelter, clothes, and warmth. 46) Then we either raise our standard of living above the necessary for comfort and happiness or leave it at this level and work shorter hours. Mankind has probably chosen the latter alternative. Men will be working shorter and shorter hours in their paid employment. And the great majority of the housewives will wish to be relieved completely of the routine operations of the home such as washing the clothes or washing up. 47) By far the most logical step to relieve the housewife of routine is to provide a robot slave which can be trained to meet the requirements of a particular home and can be programmed to carry out half a dozen or more standard operations, when so switched by the housewife. 48) It will be a machine having no more emotions than a car, but having a memory for instructions and a limited degree of instructed or built-in adaptability according to the positions in which it finds various types of objects. It will operate other more specialized machines, for example, the vacuum cleaner or clothes-washing machine. There are no problems in the production of such a domestic robot to which we do not have already the glimmering of a solution. When I have discussed this kind of device with housewives, some 90 percent of them have the immediate reaction, "How soon can I buy one?" The other 10 percent have the reaction, "I would be terrified to have it moving about my house. " 49) But when one explains to them that it could be switched off or unplugged or stopped without the slightest difficulty, or made to go and put itself away in a cupboard at any time, they quickly realize that it is a highly desirable object. 50) Now it is generally recognized that there is no greater pleasure than to go to bed in the evening and know that the washing up is being done downstairs after one is asleep. Most families are now delighted, no doubt, to have a robot slave doing all the downstairs housework after they were in bed at night.

问答题Directions:Title: The Teacher-Student RelationshipOutline:1. A good teacher-student relationship benefits both teaching and learning.2. A teacher's behaviour is important for the establishment of a good teacher-student relationship.3. What should a student do for the establishment of a good teacher-student relationship?You should write about 160-200 words neatly on ANSWER SHEET 2.

问答题Directions:Read the following text carefully and the translate the underlines segments into Chinese. Your translation should be written clearly on the ANSWER SHEET. {{U}}{{U}} 1 {{/U}}{{/U}}{{U}}It has long been suspected that only a minority of cancer cells can seed new trumours, and now the theory has finally been confirmed{{/U}}. The discovery promises to open up new avenues for developing more effective cancer therapies. In 1997, it was found that only a small subset of cancer cells taken from patients with acute leukemia can cause the disease when injected into mice. {{U}}{{U}} 2 {{/U}}{{/U}}{{U}}Intriguingly, these cells, identified by Dominique Bonnet and John Dick at the University of Toronto in Canada, were similar to the stem cells found in bone marrow that mature into blood and immune cells{{/U}}. But no such cells had ever been discovered in solid tumors such as breast cancer. Now Michael Clarke and his colleagues at the University of Michigan Medical School in Ann Arbor have found them. {{U}}{{U}} 3 {{/U}}{{/U}}{{U}}The team started by implanting tiny pieces of brest cancer tissue from nine women into the breats of female mice with weakened immune system{{/U}}. All the mice eventually developed tumours. The researchers then made up suspensions of cells taken from the tumours and injected them into mice. The suspensions contained all the cell types found in the tumour. When the mice were injected with 5000 or more cells, they caused cancer every time. But when just 1000 cells were injected, only a quarter of the mice developed tumors. This must mean that there were not enough of the cancer-causing cells in the smaller samples to initiate a tumor, Clarke reasoned. {{U}}{{U}} 4 {{/U}}{{/U}}{{U}}To zero in on the tumor-making cells, his team sorted the different cells types by using antibodies that attached to different proteins on their cell surfaces{{/U}}. They then injected the separate cell types into mice. Clarke's team found that many cell types did not cause cancer at all. But tumours were consistently produced by as few as 200 cells of a type that expressed surface proteins called CD (44) and EAS and were deficient in a protein called CD(24). {{U}}{{U}} 5 {{/U}}{{/U}}{{U}}"This small number of cells is able to give rise to a tumour just as rapidly as 50,000 unsorted cells, " says Clarke, whose findings will be published in a future issue of Proceedings of the National Academy of Sciences{{/U}}. The tumors produced by these rare cells contained the entire gamut of cells found in the original cancerous tissue, including those incapable of forming new tumors. This suggests that, like stem cells, they can make many different cell types. The cells are similar to epithelial stem cells, which also express CD (44) and ESA on their surfaces. "This has huge implications for therapeutics, " says Clarke. "We can figure out how to target these cells." Bbonnet, who now works for Cancer Research UK, calls the work "seminal".

问答题Directions: Write a letter to your general manager Mr. David, telling him that you"ve decided to quit the job as a secretary in the company. You should write about 100 words. Do not sign your own name at the end of the letter; use "Li Ming" instead. Do not write the address.

问答题(46) The determination of the sources of copper ore used in the manufacture of copper and bronze artifacts of Bronze Age civilizations would add greatly to our knowledge of cultural contacts and trade in that era when preliminary industry was on the horizon. Researchers have analyzed artifacts and ores for their concentrations of elements, but for a variety of reasons, these studies have generally failed to provide evidence of the sources of the copper used in the objects. Elemental composition can vary within the same copper-ore lode, usually because of varying admixtures of other elements, especially iron, lead, zinc, and arsenic. And high concentrations of cobalt or zinc noticed in some artifacts, appear in a variety of copper-ore sources. Moreover, the processing of ores introduced poorly controlled changes in the concentrations of minor and trace elements in the resulting metal. Some elements evaporate during smelting and roasting; different temperatures and processes produce different degrees of loss. (47) Finally, flux, which is sometimes added during smelting to remove waste material from the ore, could add to the final product quantities of elements that are mixed together with copper. An elemental property that is unchanged through these chemical processes is the isotopic composition of each metallic element in the ore. Isotopic composition, the percentages of the different isotopes of an element in a given sample of the element, is therefore particularly suitable as an indicator of the sources of the ore. (48) Of course, for this purpose it is necessary to find an element whose elemental composition is more or less constant throughout a given ore body, but varies from one copper ore body to another or, at least, from one geographic region to another. The ideal choice, when isotopic composition is used to investigate the source of copper ore, would seem to be copper itself. It has been shown that small but measurable variations occur naturally in the isotopic composition of copper. However, the variations are large enough only in rare ores; between samples of the common ore minerals of copper, isotopic variations greater than the measurement error have not been found. (49) An alternative choice is lead, which occurs in most copper and bronze artifacts of the Bronze Age in amounts consistent with the lead being derived from the copper ores and possibly from the fluxes. The isotopic composition of lead often varies from one source of common copper ore to another, with variations exceeding the measurement error; and preliminary studies indicate virtually uniform is topic composition of the lead from a single copper-ore source. (50) While some of the lead found in an artifact may have been introduced from flux or when other metals were added to the copper ore, lead so added in Bronze Age processing would usually have the same composition as the lead found in the copper ore. Lead isotope studies may thus prove useful for interpreting the archaeological record of the Bronze Age.

问答题When the Vikings invaded Great Britain, they did more than slaughter the population, ransack the cities and scorch the earth. They also left substantial influence on the English language words like slaughter, ransack and scorch. (46)Now, a single word in an ancient manuscript has led a U. S. linguist to conclude that the influence of the Norse on the English language may have come as much as a century earlier than most scholars had thought. The find came when English professor Jonathan Evans of the University of Georgia was reading a passage to his Old English class from the Anglo-Saxon Chronicle and a Norse word, theora, jumped out at him. The 1122 text, according to generations of scholars, was supposed to be too early to contain evidence of Danish influence on Old English. (47)But the fact that the text used the Nordic form of "their" rather than the Old English hiera or heora, suggested that Norsemen and their English hosts were not only living side-by-side in England's East Midlands but also were in "frequent, peaceful communication", Evans contends. "I thought I had made a mistake," when he first saw the word, he said. "There it was, sitting there in plain sight. Nobody saw this Danish word sitting there. I kept it quiet because I thought I made a mistake." But he was urged to investigate by a visiting Danish scholar, Hans Nielsen. (48)So Evans spent several years pursuing a hunch that a Roman Catholic monk slipped into the local dialect while copying out the ancient historical work for his monastery. If so, that suggests to Evans that Norse and West-Saxon dialects of Old English had mingled significantly by the 12th century if not earlier. The result of Evans' research is a paper, recently published in the journal North-Western European Language Evolution. (49)His paper puts forth the theory that the monk's use of the Norse word is the first datable example in English of Scandinavian-derived plural pronouns, antecedents of the modern English words they, them, and their. (50)" This is a footnote in a much more well-known story—the story of Scandinavian borrowings in the English language." said Evans, who can read texts in Danish, French, Old English and Old Icelandic. "It's going to be interesting to see how other scholars view this discovery but I think I've made my case for it./

问答题Outline:1. Pollution is becoming more and more serious all over the world.2. People are showing a growing concern over the problem.3. Fortunately, measures have been taken to cope with the situation.

问答题Going to the ballpark, visiting friends and playing bingo are simple diversions for many of us. But for the elderly, these social pastimes may play a critical role in preserving their physical and mental health. (46) In fact, a new study suggests that the less time older people spend engaged in social activity, the faster their motor function tends to decline. "Everybody in their 60s, 70s and 80s is walking more slowly than they did when they were 25," says Dr. Aron Buchman, a neurologist at the Rush University Medical Center in Chicago and leading author of the study, which was published in the June 22nd issue of the Archives of Internal Medicine. (47) "Our study shows the connection between social activity and motor function--and opens up a whole new universe of how we might intervene. " (48) An increasing body of evidence has suggested that participating in mentally stimulating activity, socializing frequently and exercising may help protect against age-related decline-at least cognitive decline. As early as 1995, neuroscientist Carl Cotman, who studies aging and dementia at the University of California at Irvine, published a paper in Nature showing that physical exercise produces a protein that helps keep neurons from dying and spurs the formation of new neural connections in the brain. (49) More recently, Cotman demonstrated in studies of elderly dogs and mice that enriching their social environment is associated with improvement in brain function. Researchers are also finding that social activity may be linked to the same protective effect in people. A recent study of 2 500 adults ages 70 to 79, published in the journal Neurology, found that those who were able to stay mentally sharp were also those who exercised once a week or more, had at least a ninth grade literacy level and were socially active. While further research needs to be done to establish the exact impact of social activity and exercise on specific age-related declines (50) it"s likely that a reduction in social activity may simply be a symptom of physical decline, since people may naturally withdraw from social engagement as they lose motor skills -most researchers would agree that it is not unreasonable to encourage seniors to get out there more. Only 10% of people over 65 get the recommended amount of exercise (at least 2. 5 to 5 hours a week), and given that seniors already tend to be more socially isolated than younger adults, it"s difficult to motivate them to become more active. "If you are alone, you are less likely to follow recommendations," notes Verghese. It might help, though, if you visit Grandma more often and let her know that a regular pastime may just help her stay fitter and sharper longer.