题目内容
The food we eat seems to have profound effects on our health. 【C1】______ science has made enormous steps 【C2】______ making food more fit to eat, it has, at the same time, made many foods unfit to eat. Some research has shown that perhaps eighty percent of all human【C3】______ are related to diet and forty percent of cancer is related to the diet as well,【C4】______ cancer of the colon (结肠癌). Different cultures are more prone to 【C5】______ certain illnesses because of the food that is 【C6】______ in these cultures. That food is related to illness is 【C7】______ a new discovery. In 1945, government researchers realized that nitrates and nitrites (硝酸盐和亚硝酸盐) , commonly used to preserve color in meats, and other food additives(添加剂 ) , 【C8】 ______ cancer. Yet, these carcinogenic (致癌的)additives 【C9】______ in our food, and it becomes more 【C10】______ all the time to know which things on the packaging labels of processed food are helpful or【C11】______ . The additives which we eat are not all so 【C12】______ Farmers often give penicillin (青霉素)to beef and poultry, and 【C13】______ of this, penicillin has been found in the milk of 【C14】 ______ cows. Sometimes similar drugs are 【C15】 ______ to animals not for medicinal purposes, but for 【C16】______reasons. The farmers are simply trying to 【C17】______ the animals in order to obtain a 【C18】______ price on the market. Although the Food and Drug Administration (FDA) has tried 【C19】______ to control these procedures, the practices 【C20】______ .
【C1】
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A．When the method of controlled experiment was first introduced.B．When Galileo succeed
听力原文： In science the meaning of the word "explain" suffers with civilization's every step in search of reality. Science cannot really explain electricity, magnetism, and gravitation; their effects can be measured and predicted, but of their nature is no more known to the modem scientists than to Thales who first looked into the nature of the electrification of amber, a hard yellowish-brown gum. Most contemporary physicists reject the notion that man can ever discover what these mysterious forces "really" are. Electricity, Bertrand Russell says, "is not a thing, like St. Paul's Cathedral; it is a way in which things behave. When we have told how things behave when they are electrified, and under what circumstances they are electrified, we have told all there is to tell." Until recently scientists would have disapproved of such an idea. Aristotle, for example, whose natural science dominated western thought for two thousand years, believe that man could arrive at an understanding of reality by reasoning from self-evident principles. He felt, for example, that it is a self-evident principle that everything in the universe has its proper place, hence 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 why things happen. Modem science was born when Galileo began trying to explain how things happen and thus originated the method of controlled experiment that now forms the basis of scientific investigation.
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A．The speculations of Thales.B．The forces of electricity, magnetism, land gravity.C．Ar
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.
Many of the most damaging and life threatening types of weather torrential rains, severe thunderstorms, and tornadoes begin quickly, strike suddenly, and disappear rapidly, destroying small regions while leaving neighbouring areas untouched. Such event as a tornado struck the northeastern section of Edmonton, Alberta, in July 1987. Total damages from the tornado exceeded $ 250 million, the highest ever for any Canadian storm.
Conventional computer models of the atmosphere have limited value in predicting short lived local storms like the Edmonton tornado, because the available weather data are generally not detailed enough to allow computers to study carefully the subtle atmospheric changes that come before these storms. In most nations, for example, weather- balloon observations are taken just once every twelve hours at locations typically separated by hundreds of miles. With such limited data, conventional forecasting models do a much better job predicting general weather conditions over large regions than they do forecasting specific local events.
Until recently, the observation intensive approach needed for accurate, very short -range forecasts, or "Nowcasts," was not feasible. The cost of equipping and operating many thousands of conventional weather stations was extremely high, and the difficulties involved in rapidly collecting and processing the raw weather data from such a network were hard to overcome. Fortunately, scientific and technological advances have overcome most of these problems. Radar systems, automated weather instruments, and satellites are all capable of making detailed, nearly continuous observation over large regions at a relatively low cost. Communications satellites can transmit data around the world cheaply and instantaneously, and modem computers can quickly compile and analyze this large volume of weather information. Meteorologists and computer scientists now work together to design computer programs and video equipment capable of transforming raw weather data into words, symbols, and vivid graphic displays that forecasters can interpret easily and quickly. As meteorologists have begun using these new technologies in weather forecasting offices, Nowcasting is becoming a reality.
The word "exceeded" in paragraph 1 most probably means______.
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