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Passage Five
The collapse of the Earth’s magnetic field—which guards the planet and guides many of its creatures—appears to have started seriously about 150 years ago, the New York Times reported last week.
The field’s strength has decreased by 10 or 15 per cent so far and this has increased the debate over whether it signals a reversal of the planet’s lines of magnetic force.
During a reversal, the main field weakens, almost vanishes, and reappears with opposite polarity. The transition would take thousands of years. Once completed, compass needles that had pointed north would point south. A reversal could cause problems for both man and animals. Astronauts and satellites would have difficulties. Birds, fish and animals that rely on the magnetic field for navigation would find migration confusing. But experts said the effects would not be a big disaster, despite claims of doom and vague evidence of links between past field re
A. the flows of melted iron inside the Earth
B. the periodical movement of the Earth

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[单项选择]Passage Five

The collapse of the Earth’s magnetic field—which guards the planet and guides many of its creatures—appears to have started seriously about 150 years ago, the New York Times reported last week.
The field’s strength has decreased by 10 or 15 per cent so far and this has increased the debate over whether it signals a reversal of the planet’s lines of magnetic force.
During a reversal, the main field weakens, almost vanishes, and reappears with opposite polarity. The transition would take thousands of years. Once completed, compass needles that had pointed north would point south. A reversal could cause problems for both man and animals. Astronauts and satellites would have difficulties. Birds, fish and animals that rely on the magnetic field for navigation would find migration confusing. But experts said the effects would not
A. begun to change in the opposite direction
B. been weakening in strength for a long time
C. caused the changes on the polarities
D. misguided many a man and animal

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[单项选择]Passage Five

There Pictures from outer space now show us how much land has changed on earth. These images are taken by Landsat 7, a government satellite. The satellites have been used for 27 years. They reveal the clear-cutting of forests in the northwestern part of the United States. Pictures show the loss of rain forests in South America.
NASA’s Darrel Williams speaks about the Landsat 7 Project. He said that an eruption caused trees to bum up in a large forest. Fifteen years later, pinkish images from space show that the trees and plant life are growing again. Williams says that clear-cut areas easily show up in the pictures. He wants Americans to look at how much land is being cleared of forests in our country.
Satellites have provided other information about changes on earth. In the past ten years, more than four miles have shrunk
A. sightseers have noted the changes
B. computer-animated views have shown the shrinkage
C. one of the glaciers was hit by a ship
D. the temperatures are much colder

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[单项选择]Passage Five

It was possible to define male and female roles easily by the division of labour. Men worked outside the home and earned the income to raise their families. While women cooked the meals, there was not much opportunity for men or women to exchange their roles. But by the middle of this century, men’s and women’s roles were becoming less firmly fixed.
In the 1950s, economic and social success was the aim of the typical American. But in the 1960s a new force called the counterculture (反主流文化) developed. The people involved in this movement did not value the middle-class American goals. The counterculture presented men and women with new role choices. Taking more interest in child care, men began to share child-raising tasks with their wives. Actually some young men and women moved to communal homes or farms where the economic and c
A. Women usually worked outside the home for wages
B. Men’s and women’s roles were easily exchanged in the past
C. Men’s roles at home was more firmly fixed than women’s
D. Men’s and women’s roles were usually quite separated in the past

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[单项选择]Passage Five

African American women’s search for societal acceptance often encompasses struggle between natural and socially constructed ideas of beauty. As an essential component in traditional African societies, cosmetic modification is ritualized to emphasize natural features of blackness. Defined by social occasion such as childhood development maturity, indicators of marital status or the group to which you belong, beautification of the hair and body play an essential role. In our racially conscious society, presenting a physical image and being accepted is a complex negotiation between two different worlds.
Hair is an outward expression of culture and heritage. It also represents a sense of personal style. In the search for the African American identity, blacks have undergone many different changes in hairstyle. Hairstyles are cultura
A. Because they tried to keep socially fashionable.
B. Because they did not have their own standards of beauty.
C. Because they were not well educated as white Americans.
D. Because they wanted to become part of the mainstream.

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[简答题]Passage Five

After the violent earthquake that shook Los Angeles in 1994, earthquake scientists had good news to report: The damage and death toll could have been much worse.
More than 60 people died in this earthquake. By comparison, an earthquake of similar intensity that shook America in 1988 claimed 25 000 victims.
Injuries and deaths were relatively less in Los Angeles because the quake occurred at 4: 31 a.m. on a holidays, when traffic was light on the city’ s highways. In addition, changes made to the construction codes in Los Angeles during the last 20 years have strengthened the city’s buildings and highways, making them more resistant to quakes.
Despite the good news, civil engineers aren’t resting on their successes. Pinned(别住，钉住) to their drawing boards are blueprints (蓝图) for improved quake-resistant (抗震的) buildings. The new designs should offer even greater security to cities where earthquakes often take place.
I

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