单选题—I wonder how much you charge for your service. —The first two are free ______ the third costs $50. A. when B. until C. while D. before

单选题What can we learn from Paragraph 2?

单选题{{B}}Passage 4{{/B}} Many United States companies have, unfortunately, made the search for legal protection from import competition into a major line of work. Since 1980 the United States International Trade Commission (ITC) has received about 280 complaints alleging damage from imports that benefit from subsidence by foreign governments. Another 340 charge that foreign companies "dumped" their products in the United States at “less than fair value”. Even when no unfair practices are all alleged, the simple claim that an industry has been injured by imports is sufficient grounds to seek relief. Contrary to the general impression, this quest for import relief has hurt more companies than it has helped. As corporations begin to function globally, they develop an intricate Web of marketing, production, and research relationships. The complexity of these relationships makes it unlikely that a system of import relief laws will meet the strategic needs of all the units under the same parent company. Internationalization increases the danger that foreign companies will use import relief laws against the very companies the laws were designed to protect. Suppose a United States-owned company establishes an overseas plant to manufacture a product while its competitor makes the same product in the United States. If the competitor can prove injury from the imports--and that the United States company received a subsidy from a foreign government to build its plant abroad--the United States company's products will be uncompetitive in the United States, since they would be subject to duties. Perhaps the most brazen case occurred when the ITC investigated allegations that Canadian companies were injuring the United States salt industry by dumping rock salt, used to deice roads. The bizarre aspect of the complaint was that a foreign conglomerate with United States operations was crying for help against a United States company with foreign operations. The "United States" company claiming injury was a subsidary of a Dutch conglomerate, while the "Canadian" companies included a subsidary of a Chicago firm that was the second largest domestic producer of rock salt.

单选题{{B}}Passage 4{{/B}} Surgeons will soon be able to enter the eye to carry out operations--at least in a virtual sense. Techniques derived from virtual reality--the computer system that immerses operations in an artificial computer-generated world--will allow surgeons to feel as if he could see the inside of the eye during an operation, creating the illusion that they are actually there. Researchers at the Biorobotics Laboratory of McGill University in Montreal are building a robot, known as Micro Surgery robot - 1 (MSR - I for short), that will perform delicate operations under the control of a human surgeon. The robot is specifically designed for performing eye surgery but could have other applications, such as the removal of brain tumors. The system could also be used to allow surgeons and their students to practise simulated surgery that feel like the real thing-without the real consequences for the patients. During the operations, the surgeon manipulates a set of control known as the master. These are connected through a high-performance computer to the robot. Both the master and the robot have two limbs, When the surgeon moves the masters' limbs, the robots limbs move in exactly the same way, except that the movements can be scaled down as much as a thousand times. This will eliminate hand tremor and poor accuracy and thus reduce the damage to the eye that can occur with present microsurgery techniques. Each of the robots limbs has a minimum movement of one micrometer--more than one hundred times the precision of the human hand. The computer also creates a three-dimensional robot' s eye view of the inside of the eye that the surgeon can see by wearing a virtual reality helmet that has a small lens in front of each eye. To provide the surgeon with such a realistic experience, MSR-I must be able to move rapidly, but this requires extremely fast computing. To handle the computational demands of instant interaction, the McGill team is constructing its own parallel-processing computer. It is also studying areas such as muscle mechanism, artificial intelligence and optics, and has a already built another micro robot MR-I, capable of manipulating a single living cell. Although commercial applications of the new system are not expected for several years, its basic mechanical components will be ready for testing in a few months, "The day when micro-robots will be able to perform surgery without human intervention is many years away," says Hunter, "in the meantime, a system such as MRS-I is a necessary precursor."

单选题Questions 17—20 are based on the following talk on the economy of southern America. You now have 20 seconds to read Questions 17—20.

单选题Questions 14-16 are based on the following passage. You now have 15 seconds to read Questions 14-16.

单选题No one can deny that pesticides have improved the ability of farmers to bring their crops to market. (1) pesticides, farmers no longer have to worry that they will lose an entire crop (2) an army of cut worms(毛虫)or fruit flies. (3) , Americans can rely on a large and varied food supply. However, we Americans need to become more (4) about the effects those pesticides on our food. More (5) , we need to think about what new (6) is necessary to protect ourselves from a (7) too rich in pesticide residue. If we don't demand greater (8) on pesticide use, we may be surprised, dismayed, and (9) horrified by the consequence of its use. On the most obvious level, farm workers who continue to use the pesticides (10) their present rate will be (11) serious disease. It's no (12) that farmers (13) to herbicides: have a six times greater risk of getting cancer. (14) , children who live in homes where pesticides are used have an increased chance of getting childhood leukemia (白血病). But the farmers are not the only ones (15) risk. Consumers may also suffer serious side effects from daily (16) of foods tainted (污染) by pesticides. Although scientists have yet to prove the link (17) , they are concerned that pesticide use may be one reason for the starting increase in various forms of cancer like breast and colon (结肠) cancers. We need new legislating that (18) stricter standards governing pesticide residues in food. Much of the current legislation is based on ignorance. Simply (19) , we allow high levels of carcinogens (致癌物) in our food because we don't know for sure that they do cause cancer in humans. Yet, why should we take the risk? If there's a chance that a pesticide causes cancer, then it should be (20) from use.

单选题 {{I}} Questions 17--20 are based on the following passage. You now have 20 seconds to read Questions 17--20.{{/I}}

单选题How is the situation likely to affect the future of science?

单选题What does the phrase" on the ropes" ( L7, Para2 ) mean?

单选题Sleep plays a major role in preparing the body for an alert and productive tomorrow. But sleep is not a period of inactivity. The sleeping brain is highly active at various times during the night, performing numerous "house keeping tasks". These keep us alive and aid our ability to think and remember. Sleep also energizes the body and brain. Most people spend one-third of their lives sleeping and this will affect the other two-thirds in terms of alertness, energy, moods, body weight, perception, memory, thinking, reaction time, productivity and performance. To limit sleep means our health and daytime potential are significantly reduced. So, good sleep strategies are essential in order to feel energized day after day. There is no strategy which works for everyone, so each person needs to experiment. One important thing is that you shouldn't worry too much if you go a few nights without a lot of sleep. It won't ruin your life. On any given night, one in four people can't sleep properly and everyone suffers from a lack of sleep at some time. How does one minimize this problem? It is really quite simple. The first thing you must do is to reduce stress as much as possible. Stress is part of everyday life and, while we can never be entirely without stress, it can be managed. This means taking control of your life and focusing on what is important. One sleeping strategy is to sit in a comfortable position, close your eyes and relax all your muscles, breathing easily through your nose. Continue this for ten to twenty minutes. This should help you reduce stress and sleep better. Or, you can try getting plenty of exercise, because a tired body is likely to sleep better.

单选题He was born in ______south of China, but later he moved to ______north. [A] the; the [B] the; / [C] /; the

单选题Caffeine ______ if you want to have a good sleep.

单选题What happens when quarrels over job opportunities arise among British unions?

单选题The local inhabitants think tourists shameless because______.