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It has been known for many decades that the appearance of sunspots is roughly periodic, with an average cycle of eleven years. Moreover, the incidence of solar flares and the flux of solar cosmic rays, ultraviolet radiation, and X-radiation all vary directly with the sunspot cycle. But after more than a century of investigation, the relation of these and other phenomena, known collectively as the solar-activity cycle, to terrestrial weather and climate remains unclear. For example, the sunspot cycle and the allied magnetic-polarity cycle have been linked to periodicities discerned in records of such variables as rainfall, temperature, and winds. Invariably, however, the relation is weak, and commonly of dubious statistical significance.Effects of solar variability over longer terms have also been sought. The absence of recorded sunspot activity in the notes kept by European observers in the late seventeenth and early eighteenth centuries has led some scholars to postulate a brief cessation of sunspot activity at that time (a period called the Maunder minimum). The Maunder minimum has been linked to a span of unusual cold in Europe extending from the sixteenth to the early nineteenth centuries. The reality of the Maunder minimum has yet to be established. However, especially since the records that Chinese naked-eye observers of solar activity made at that time appear to contradict it. Scientists have also sought evidence of long-term solar periodicities by examining indirect climatological data, such as fossil records of the thickness of ancient tree rings. These studies, however, failed to link unequivocally terrestrial climate and the solar-activity cycle, or even to confirm the cycle’s past existence.If consistent and reliable geological or archaeological evidence tracing the solar-activity cycle in the distant past could be found, it might also resolve an important issue in solar physics: how to model solar activity. Currently, there are two models of solar activity. The first supposes that the Sun’s internal motions (caused by rotation and convection) interact with its large-scale magnetic field to produce a dynamo, a device in which mechanical energy is converted into the energy of a magnetic field. In short, the Sun’s large-scale magnetic field is taken to be self-sustaining, so that the solar-activity cycle it drives would be maintained with little overall change for perhaps billions of years. The alternative explanation supposes that the Sun’s large-scale magnetic field is a remnant of the field the Sun acquired when it formed, and is not sustained against decay. In this model, the solar mechanism dependent on the Sun’s magnetic field runs down more quickly. Thus, the characteristics of the solar-activity cycle could be expected to change over a long period of time. Modern solar observations span too short a time to reveal whether present cyclical solar activity is a long-lived feature of the Sun, or merely a transient phenomenon.1. The author focuses primarily on ________.2. Which of the following statements about the two models of solar activity, as they are described in Para. 3, is accurate?3. According to the passage, late seventeenth and early eighteenth centuries Chinese records are important for which of the following reasons?4. It can be inferred from the passage that studies attempting to use tree-ring thickness to locate possible links between solar periodicity and terrestrial climate are based on which of the following assumptions?

To live in the United States today is to gain an appreciation for Dahrendorf’s assertion that social change exists everywhere. Technology, the application of knowledge for practical ends, is a major source of social change.Yet we would do well to remind ourselves that technology is a human creation; it does not exist naturally. A spear or a robot is as much a cultural as a physical object. Until humans use a spear to hunt game or a robot to produce machine parts, neither is much more than a solid mass of matter. For a bird looking for an object on which to rest, a spear or robot serves the purpose equally well. The explosion of the Challenger space shuttle and the Russian nuclear accident at Chernobyl drive home the human quality of technology; they provide cases in which well-planned systems suddenly went haywire (变得混乱) and there was no ready hand to set them right. Since technology is a human creation, we are responsible for what is done with it. Pessimists worry that we will use our technology eventually to blow our world and ourselves to pieces. But they have been saying this for decades, and so far we have managed to survive and even flourish. Whether we will continue to do so in the years ahead remains uncertain. Clearly, the impact of the technology on our lives deserves a closer examination.Few technological developments have had a greater impact on our lives than the computer revolution. Scientists and engineers have designed specialized machines that can do the tasks that once people could do. There are those who assert that the switch to an information-based economy is in the same camp as other great historical milestones, particularly the Industrial Revolution. Yet when we ask why the Industrial Revolution was a revolution, we find that it was not the machines. The primary reason why it was revolutionary is that it led to great social change. It gave rise to mass production and, through mass production, to a society in which wealth was not confined to the few.In somewhat similar fashion, computers promise to revolutionize the structure of American life, particularly as they free the human mind and open new possibilities in knowledge and communication. The Industrial Revolution supplemented and replaced the muscles of humans and animals by mechanical methods. The computer extends this development to supplement and replace some aspects of the mind of human beings by electronic methods. It is the capacity of the computer for solving problems and making decisions that represents its greatest potential and that poses the greatest difficulties in predicting the impact on society.1. A spear or a robot has the quality of technology only when it .2. The examples of the Challenger and Chernobyl cited by the author serve to show that .3. According to the author, the introduction of the computer is a revolution mainly because .4. By using the phrase “the human quality of technology” (Para. 2), the author refers to the fact that technology .

When imaginative men turn their eyes towards space and wonder whether life exists in any part of it, they may cheer themselves by remembering that life need not resemble closely the life that exists on Earth. Mars looks like the only planet where life like ours could exist, and even this is doubtful. But there may be other kinds of life based on other kinds of chemistry, and they may multiply on Venus or Jupiter. At least we cannot prove at present that they do not.Even more interesting is the possibility that life on their planets may be in a more advanced stage of evolution. Present-day man is in a peculiar and probably temporary stage. His individual units retain a strong sense of personality. They are, in fact, still capable under favorable circumstances of leading individual lives. But man’s societies are already sufficiently developed to have enormously more power and effectiveness than the individuals have.It is not likely that this transitional situation will continue very long on the evolutionary time scale. Fifty thousand years from now man’s societies may have become so close-knit that the individuals retain no sense of separate personality. Then little distinction will remain between the organic parts of the multiple organism and the inorganic parts (machines) that have been constructed by it. A million years further on man and his machines may have emerged as closely as the muscles of the human body and the nerve cells that set them in motion.The explorers of space should be prepared for some such situation. If they arrive on a foreign planet that has reached an advanced stage (and this is by no means impossible), they may find it being inhabited by a single large organism composed of many closely cooperating units.The units may be “secondary”—machines created millions of years ago by a previous form of life and given the will and ability to survive and reproduce. They may be built entirely of metals and other durable materials. If this is the case, they may be much more tolerant of their environment, multiplying under conditions that would destroy immediately any organism made of carbon compounds and dependent on the familiar carbon cycle.Such creatures might be relics of a past a past age, many millions of years ago, when their planet was favorable to the origin of life, or they might be immigrants from a favored planet.1. Humans on Earth today are characterized by .2. According to the passage, some people believe that eventually .3. Even most imaginative people have to admit that .4. It seems that the writer .

The speaker, a teacher from a community college, addressed a sympathetic audience. Heads nodded in agreement when he said, “High school English teachers are not doing their jobs.” He described the inadequacies of his students, all high school graduates who can use language only at a grade 9 level. I was unable to determine from his answers to my questions how this grade 9 level had been established.My topic is not standards nor its decline. What the speaker was really saying is that he is no longer young; he has been teaching for sixteen years, and is able to think and speak like a mature adult.My point is that the frequent complaint of one generation about the one immediately following it is inevitable. It is also human nature to look for the reasons for our dissatisfaction. Before English became a school subject in the late nineteenth century, it was difficult to find the target of the blame for language deficiencies. But since then, English teachers have been under constant attack.The complainers think they have hit upon an original idea. As their own command of the language improves, they notice that young people do not have this same ability. Unaware that their own ability has developed through the years, they assume the new generations of young people must be hopeless in this respect. To the eyes and ears of sensitive adults the language of the young always seems inadequate.Since this concern about the decline and fall of the English language is not perceived as a generational phenomenon but rather as something new and peculiar to today’s young people, it naturally follows that today’s English teachers cannot be doing their jobs. Otherwise, young people would not commit offenses against the language.1. The speaker the author mentioned in the passage believed that .2. In the author’s opinion, the speaker .3. It can be concluded from the passage that .4. The author’s attitude towards the speaker’s remarks is .

Directions: Use about 250 words to give your comment on the following situation.Dong Pan, a professor of Beijing Normal University as well as a doctoral tutor, posted a micro blog on April 4, 2011, claiming “I have a requirement for my graduate students that if you do not have an individual net worth of 40 million yuan by the age of 40, please do not come to see me and do not tell others you are my students.” Please use specific reasons and examples to support your opinion.

As an adult I once did the same thing to Sophia, calling her garbage in English when she acted extremely disrespectfully toward me. When I mentioned that I had done this at a dinner party, I was immediately ostracized (excluded). One guest named Marcy got so upset she broke down in tears and had to leave early. My friend Susan, the host, tried to rehabilitate me with the remaining guests.The fact is that Chinese parents can do things that would seem unimaginable—even legally actionable (可起诉的)—to Westerners. Chinese mothers can say to their daughters, “Hey fatty—lose some weight.” By contrast, Western parents have to tiptoe around the issue, talking in terms of “health” and never ever mentioning the f-word, and their kids still end up in therapy for eating disorders (进食障碍) and negative self-image. (I also once heard a Western father toast his adult daughter by calling her “beautiful and incredibly competent”. She later told me that made her feel like garbage.)Chinese parents can order their kids to get straight As. Western parents can only ask their kids to try their best. Chinese parents can say, “You’re lazy. All your classmates are getting ahead of you.” By contrast, Western parents have to struggle with their own conflicted feelings about achievement, and try to persuade themselves that they’re not disappointed about how their kids turned out.I’ve thought long and hard about how Chinese parents can get away with what they do. I think there are three big differences between the Chinese and Western parental mind-sets (心态，思维定式，思维取向).

Higher interest rates make it more expensive to borrow money, ________ people from buying new homes or starting new construction projects. (courage)

The effort to clarify the bewildering number of interrelated observations ________ by psychoanalytic exploration led to the development of a model of the structure of the psychic system. (cover)

The situation comedy (or sitcom) depends on audience ________ with recurring characters and conditions to explore life in the home, workplace, or some other common location. (familiar)

People with depression may have low self-esteem, a sense of hopelessness about the future, and a lack of interest in people and activities once found ________. (pleasure)

While Mexico’s overall economic ________ showed an increase in foreign trade after the institution of NAFTA, real wages continued to fall throughout the country and poverty rates remained constant. (indicate)

Economists are now realizing the full extent which the communications revolution has affected the world economy. Information technology allows the extension of trade across geographical and industrial boundaries, and transnational A B Ccorporations take full advantage of it. D

The effect of all this on the food situation in this country has been made worse by a simultaneous rise in foods prices, due chiefly to the gradual cutting down of government support for food. A B C D

It seems that there is no set of personal qualities that all leaders have something in common; rather, virtually any person may be recognized as a leader if the person has qualities that meet the needs of that particular group. A B C D

In addition, changes made to the construction codes in Los Angeles during the last 20 years have strengthened the city’s buildings and highways, to make them more resistant to quakes. A B C D

Competition protects the freedom of the individual from ensuring that there is no monopoly of power. In contrast to one, all-powerful government, many businesses compete against each other for profits. A B C D

The recent growth of export surpluses on the world food market has been unexpected great, partly because a strange sequence of two successful grain harvests in North America is now being followed by a third. A B C D

Many authors have argued for the inevitability of war from the premise that in the struggle for existence among animal species, only the fittest survival. In general however, this struggle in nature is competition, not conflict. A B C D

Since competition is seen as the major source of progress and prosperity by most Americans, competitive business institutions are respected. Competition is not only good in itself, it is the means which other basic American values such A B C Das individual freedom, equality of opportunity, and hard work are protected.

In the last 15 years, pilots have reported well over 100 incidents that could have been caused by electromagnetic interference. The source of this interference remains uncomforting, but increasingly, experts are pointing the blame at A B C Dportable electronic devices.

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