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【C18】
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In science the meaning of the word "explain" suffers 【C1】______civilization's every step in search of reality. Science cannot really explain electricity, magnetism, and gravitation; their effects can be 【C2】______ and predicted, but 【C3】______their nature no more is known to the modern scientist than to Thales who first 【C4】______the nature of the electrification of amber, a hard, 【C5】______ brown gum. Most contemporary physicists reject the 【C6】______ that man can ever discover 【C7】______these mysterious forces "really" are. Electricity, Bertrand Russell says, "is not 【C8】______thing, like St. Paul's Cathedral; it is a way 【C9】______ which things behave. When we have told how things behave when they are electrified, and 【C10】______ what circumstances they are electrified, we have told all 【C1】______ to tell." Until recently scientists would have 【C12】______of such an idea. Aristotle, for example, 【C13】______natural science dominated Western thought for two thousand years, believed that man 【C14】______rrive, at an understanding of reality by 【C15】______from self-evident principles. He felt, for example, that it is a self-evident principle that everything in the universe has its proper place, 【C16】______one can deduce that objects fall to the ground because that's where they belong, and smoke goes up because that's where it belongs. The goal of Aristotelian science was to explain 【C17】______things happen. Modem science was born when Galileo began 【C18】______to explain how things happen and thus originated the method of 【C19】______experiment which now forms the 【C20】______of scientific investigation.
【C1】
Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
Much of Canada' s forestry production goes towards making pulp and paper. According to the Canadian Pulp and Paper Association, Canada supplies 34% of the world' s wood pulp and 49% of its newsprint paper. If these paper products could be produced in some other way, Canadian forests could be preserved. Recently, a possible alternative way of producing paper has been suggested by agriculturalists and environmentalists: a plant called hemp.
Hemp has been cultivated by many cultures for thousands of years. It produces fibre which can be made into paper, fuel, oils, textiles, food, and rope. For centuries, it was essential to the economies of many countries because it was used to make the ropes and cables used on sailing ships; colonial expansion and the establishment of a world - wide trading network would not have been feasible without hemp. Nowadays, ships' cables are usually made from wire or synthetic fibres, but scientists are now suggesting that the cultivation of hemp should be revived for the production of paper and pulp. According to its proponents, four times as much paper can be produced from land using hemp rather than trees, and many environmentalists believe that the large- scale cultivation of hemp could reduce the pressure on Canada's forests.
However, there is a problem: hemp is illegal in many countries of the world. This plant, so useful for fibre, rope, oil, fuel and textiles, is a species of cannabis, related to the plant from Which marijuana is produced. In the late 1930s,a movement to ban the drug marijuana began to gather force, resulting in the eventual banning of the cultivation not only of the plant used to produce the drug, but also of the commercial fibre - producing hemp plant. In fact, marijuana cannot, be produced from the hemp plant, since it contains almost no THC (the active ingredient in the drug).
In recent years, a movement for legalization have been gathering strength. It is concerned only with the hemp plant used to produce fibre; this group wants to make it legal to cultivate the plant and sell the fibre for paper and pulp production.
Why is pulp and paper production important to Canada？
A．When the glasses are 25% full.B．When the glasses are empty.C．Before you make a toast
听力原文： The great advance in rocket theory 40 years ago showed that liquid-fuel rockets were far superior in every respect to the skyrocket with its weak solid fuel, the only kind of rocket then known. However, during the last decade, large solid-fuel rockets with solid fuels about as powerful as liquid fuels have made their appearance, and it is a favorite layman's question to inquire which one is "better". The question is meaningless; one might as well as ask whether a gasoline or a diesel engine is "better". It all depends on the purpose. A liquid-fuel rocket is complicated, but has the advantage that it can be controlled beautifully. The burning of the rocket engine can be stopped completely; it can be reignited when desired. A solid-fuel rocket, on the other hand, is rather simple in construction, though hard, to build when a really large size is desired. But once you have a solid-fuel rocket, it is ready for action at a very short notice. A liquid-fuel rocket has to be fueled first and can not be held in readiness if or very long after it has been fueled. However, once a solid-fuel rocket has been ignited, it will keep burning. It can't be stopped and reignited whenever desired. Because a solid-fuel rocket can be kept ready for a long time, most military missiles employ solid fuels, but manned space flight needs the fine adjustments that can only be provided by liquid-fuel rocket. It may be added that a liquid-fuel rocket is an expensive device; a large solid-fund rocket is, by comparison, cheap.
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