单选题The theory of meaning which relates the meaning of a word to the thing it refers to, or stands for, is known as the referential theory. (北二外2006研)

单选题She is pleased with what you have given her husband and______you have fold him.

单选题Sustainable development is applied to just about everything from energy to clean water and economic growth, and as a result it has become difficult to question either the basic assumptions behind it or the way the concept is put to use. This is especially true in agriculture, where sustainable development is often taken as the sole measure of progress without a proper appreciation of historical and cultural perspectives. To start with, it is important to remember that the nature of agriculture has changed markedly throughout history, and will continue to do so. Medieval agriculture in northern Europe led, clothed and sheltered a predominantly rural society with a much lower population density than it is today. It had minimal effect on biodiversity, and any pollution it caused was typically localized. In terms of energy use and the nutrients captured in the product it was relatively inefficient. Contrast this with farming since the start of the industrial revolution. Competition from overseas led farmers to specialize and increase yields. Throughout this period food became cheaper, safe and more reliable. However, these changes have also led to habitat loss and to diminishing biodiversity. What"s more, demand for animal products in developing countries is growing so fast that meeting it will require an extra 300 million tons of grain a year by 2050. Yet the growth of cities and industry is reducing the amount of water available for agriculture in many regions. All this mean that agriculture in the 21st century will have to be very different from how it was in the 20st. This will require radical thinking. For example, we need to move away from the idea that traditional practices are inevitably more sustainable than new ones. We also need to abandon the notion that agriculture can be "zero impact". The key will be to abandon the rather simple and static measures of sustainability, which centre on the need to maintain production without increasing damage. Instead we need a more dynamic interpretation, one that looks at the pros and cons of all the various ways land is used. There are many different ways to measure agricultural performance besides food yield: energy use, environmental cost, water purity, carbon footprint and biodiversity. It is clear, for example, that the carbon of transporting tomatoes from Spain to the UK is less than that of producing them in the UK with additional heating and lighting. But we do not know whether lower carbon footprints will always be better for biodiversity. What is crucial is recognizing that sustainable agriculture is not just about sustainable food production.

单选题Three years______before he returned home from the United States. A. denoted B. destined C. elapsed D. enveloped

单选题A really good day for Rob Borucki will be a day

单选题Passage 9 According to a survey, which was based on the responses of over 188,000 students, today's traditional-age college freshmen are "more materialistic and less altruistic (利他主义的)"than at any time in the 17 years of the poll. Not surprising in these hard times, the student's major objective "is to be financially well off. Less important than ever is developing a meaningful philosophy of life." It follows then that today the most popular course is not literature or history but accounting. Interest in teaching, social service and the "altruistic" fields is at a low. On the other hand, enrollment in business programs, engineering and computer science is way up. That's no surprise either. A friend of mine (a sales representative for a chemical company) was making twice the salary of her college instructors her first year on the job--even before she completed her two-year associate degree. While it's true that we all need a career, it is equally true that our civilization has accumulated an incredible amount of knowledge in fields far removed from our own and that we are better for our understanding of these other contributions--be they scientific or artistic. It is equally true that, in studying the diverse wisdom of others, we learn how to think. More important, perhaps, education teaches us to see the connections between things, as well as to see beyond our immediate needs. Weekly we read of unions who went on strike for higher wages, only to drive their employer out of business. No company; no job. How shortsighted in the long run! But the most important argument for a broad education is that in studying the accumulated wisdom of the ages, we improve our moral sense. I saw a cartoon recently which shows a group of businessmen looking puzzled as they sit around a conference table; one of them is talking on the intercom (对讲机) : "Miss Baxter," he says, "could you please send in someone who can distinguish right from wrong?" From the long-term point of view, that's what education really ought to be about.

单选题He was brought up ______ worker.

单选题Before coming to India the writer ______.

单选题{{B}}Passage Two{{/B}} Every living thing has an inner biological clock that controls behavior. The clock works all the time even when there are no outside signs to mark the passing of time. The biological clock tells plants when to form flowers and when the flowers should open. It tells insects when to leave the protective cocoon and fly away. And it tells animals when to eat, sleep and wake. It controls body temperature, the release of some hormones and even dreams. These natural daily events are circadian rhythms. Man has known about them for thousands of years. But the first scientific observation of circadian rhythms was not made until 1729. In that year French astronomer, Jean-Jacques d'Ortous de Mairan, noted that one of his plants opened its leaves at the same time every morning, and closed them at the same time every night. The plant did this even when he kept it in a dark place all the time. Later scientists wondered about circadian rhythms in humans. They learned that man's biological clock actually keeps time with a day of a little less than 25 hours instead of the 24 hours on a man-made clock. About four years ago an American doctor, Eliot Weitzman, established a laboratory to study how our biological clock works. The people in his experiments are shut off from the outside world. They are free to listen to and live by their circadian rhythms. Dr. Weitzman hopes his research will lead to effective treatments for common sleep problems and sleep disorders caused by aging and mental illness. The laboratory is in the Monteflore Hospital in New York City. It has two living areas with three small rooms in each. The windows are covered, so no sunlight or moonlight comes in. There are no radios or television receivers. There is a control room between the living areas. It contains computers, one-way cameras and other electronic devices for observing the person in the living area. The instruments measure heartbeat, body temperature, hormones in the blood, other substances in the urine and brain waves during sleep. A doctor or medical technician is on duty in the control room 24 hours a day during an experiment They do not work the same time each day and are not permitted to wear watches, so the person in the laboratory has no idea what time it is. In the first four years of research, Dr Weitzman and his assistant have observed 16 men between the ages of 21 and 80. The men remained in the laboratory for as long as six months. Last month, a science reporter for The New York Times newspaper, Dava Sobol, became the first woman to take part in the experiment. She entered the laboratory on June 13th and stayed for 25 days. Miss Sobol wrote reports about the experiment during that time, which were published in the newspaper.

单选题______ the teacher's suggestion, Tom finally found a way to settle the problem. A. Following B. To follow C. Follow D. He followed

单选题(2010) Shanghai is one of the important____and financial centers of the world.

单选题One of the most common techniques is to add alloying elements that Uinhibit/U the corrosion.

单选题If you don't take away all your things from the desk, there won't be enough ______ for my stationary.A. areaB. placeC. roomD. surface

单选题It ______ Tom drives badly.A. thinks thatB. is thought whatC. thought thatD. is thought that