题目内容
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"This practice" in Paragraph 4 refers to_______.
A.that farmers have lowered the yield of corn and soybean
B.that farmers have expanded croplands
C.that farmers have applied more chemical fertilizers
D.that the top soil has been decreased greatly
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第1题
the country's leading export. American farmers manage to feed not only the total population of the United States, but also millions of other people throughout the rest of the world. Corn and soybean exports alone account for approximately 75 percent of the amount sold in world markets. This productivity, however, has its price. Intensive cultivation exposes the earth to the damaging forces of nature. Every year wind and water remove tons of rich soil from the nation's croplands. Each field is covered by a limited amount of topsoil, the upper layer of earth which is richest in the nutrients and minerals necessary for growing crops. Ever since the first farmers arrived in the Midwest almost 200 years ago，cultivation and, consequently, erosion have been decreasing the supply of topsoil. In the 1830s, nearly two feet of rich, black top soil covered the Midwest. Today the average depth is only eight inches, and every decade another inch is blown or washed away. This erosion is steadily decreasing the productivity of valuable cropland. A United States Agricultural Department survey states that if erosion continues at its present rate, corn and soybean yields in the Midwest may drop as much as 30 percent over the next 50 years. So far, farmers have been able to compensate for the loss of fertile topsoil by applying more chemical fertilizers to their fields; however, while this practice has increased crop yields, it has been devastating for ecology. Agriculture has become one of the biggest polluters of the nation's precious water supply. Rivers, lakes, and underground reserves of water are being filled in and poisoned by soil and chemicals carried by drainage from eroding fields. Furthermore, fertilizers only replenish the soils they do not prevent its loss. The last sentence in the first paragraph gives an example to show_______.
A.that American farmers manage to feed the total population of the U. S.
B.the leading position of the U. S. farming in the world
C.how important American people consider their farming
D.that many people in the world rely on the export of the agricultural products of the U. S. A.
第2题
The closest restatement of the last sentence in,the 3rd paragraph is______.
A.many women would hate to be the chairperson without considering their husband's careers
B.many governors' wives complain they have to accept the chairperson roles
C.many women are forced to become the leaders of women's organizations in order to protect their husband's profession
D.many governors' wives feel it necessary to accept the roles
第3题
In the 2nd paragraph "roads" means_______.
A.some roads
B.high ways
C.country roads
D.heavy roads
第4题
Newcomers may worry about_________.
A.their ignorance of the alien customs
B.their knowledge of "yes" in the native language
C.their understanding of friendship
D.their control of their behavior
第5题
People with college education______.
A.are not happier than those who have only an education at high school
B.are much happier than those who did not graduate from high school
C.have less opportunity to control their lives
D.have more opportunity to control their lives
第6题
ecent polls (民意测验) sixty to seventy percent of Americans consider themselves to be moderately happy and one in twenty persons feels very unhappy. Psychologists have been studying the factors that contribute to happiness. It is not predictable nor is a person in an apparently ideal situation necessarily happy. The ideal situation may have little to do with his actual feelings. A good education and income are usually considered necessary for happiness. Though both may contribute, they are only chief factors if the person is seriously undereducated or actually suffering from lack of physical needs. The rich are not likely to be happier than the middle-income group or even those with very low incomes. People with college educations are somewhat happier than those who did not graduate from high school, and it is believed that this is mainly because they have more opportunity to control their lives. Yet people with a high income and a college education may be less happy than those with the same income and no college education. Poor health does not rule out happiness except for the severely disabled or those in pain. Learning to cope with a health problem can contribute to happiness. Those with a good sex life are happier in general, but those who have a loving, affectionate relationship are happier than those who rely on sex alone. Love has a higher correlation with happiness than any other factor. It should be noted that people quickly get used to what they have, and they are happiest when they feel they are increasing their level no matter where it stands at a given time. Children whose parents were happily married have happier childhoods are not necessarily happier adults. The best formula for happiness is to be able to develop the ability to tolerate frustration, to have a personal involvement and commitment, and to develop self-confidence and self-esteem. It can be inferred from the passage that______.
A.happiness is predictable
B.a person in an apparently ideal situation must be happy
C.the rich are likely to be happier than the middle-income group
D.happiness is not necessarily connected to one's situation in society
第7题
To check population growth is necessary when_______.
A.there are decreasing productivity gains
B.there are increasing productivity losses
C.we are close to reaching the sustainability limits at a world level
D.people become a cost
第8题
By "infrastructure"(Para. 2) the author means_______.
A.buildings
B.the basic framework of a country, such as schools, services, etc.
C.social demands
D.services and production
第9题
Which of the following is TRUE according to the first paragraph?
A.Mexico has stepped into an aging society.
B.It is not necessary for Mexico to control its population.
C.Mexico population is younger than that of developed countries.
D.It is not necessary for Mexico to develop its infrastructure.
第10题
of social demands. However, Mexico will still be far from the "aging societies" that will most likely prevail (占优势 ) in the industrialized countries. In less than 25 years, the country will have to add almost as much infrastructure as it has already built up to now, simply to maintain services and production at the current levels. This will be a tremendous challenge, although a similar one was faced successfully in the recent past, when available infrastructure was doubled in two decades or so. It is no wonder that much has been said about the need to reduce or preferably halt Mexico's population control which is taken for granted as both good and necessary. It has also gained supporters in the developing world, and Mexico is no exception. But the arguments about population are complicated, as the following discussion illustrates. Even if Mexico's population reaches 125 million by the year 2010, its population density is still smaller than the 1985 population density of some 50 countries. By international standards Mexico will still not be overpopulated by the year 2010. If wealth is generated by people, the more individuals there are, the greater the wealth that potentially could be generated. Why should Mexico control its population at density levels below those of the richer countries if more population represents the possibility of generating more wealth? On the other hand, it is often pointed out that once sustainability(支撑力) limits are near or are reached, there are decreasing productivity gains (or,perhaps more accurately, increasing productive losses) , and people become a cost rather than an asset. If we assume that there are sustainability limits and that we are close to reaching these limits at a world level, then it is appropriate to check population growth. According to the passage, the population argument is focused on_______.
A.whether more people are a property or a cost
B.whether Mexico should control its population growth or not
C.whether the density of population in Mexico is large or small
D.what the standard international sustainability limit is
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