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《明史·职官一》记载:明代内阁的职权为“献替可否，奉陈规诲，点检题奏，票拟批答，以平允庶政”。其中，“献”是大学士根据皇帝的咨询，发表意见，“替否”是指大学士对皇帝所采取的意见措施持不同观点。以上材料说明了：

A．明代内阁大学士都是皇帝及太子的老师

B．明代内阁首辅就是宰相

C．明代内阁是为皇帝提供顾问的内侍机构

D．明代内阁权力大于皇权

We are not who we think we are.

The American self-image is spread with the golden glow of opportunity. We think of the United States as a land of unlimited possibility, not so much a classless society but as a place where class is mutable—a place where brains, energy and ambition are what counts, not the circumstances of one's birth.

The Economic Mobility Project, an ambitious research led by Pew Charitable Trusts, looked at the economic fortunes of a large group of families over time, comparing the income of parents in the late 1960s with the income of their children in the late 1990s and early 2000s. Here is the finding: "The 'rags to riches' story is much more common in Hollywood than on Main Street. Only 6 percent of children born to parents with family income at the very bottom move to the top.

That is right, just 6 percent of children born to parents who ranked in the bottom of the study sample, in terms of income, were able to bootstrap their way into the top . Meanwhile, an incredible 42 percent of children born into that lowest are still stuck at the bottom, having been unable to climb a single rung of the income ladder.

It is noted that even in Britain---a nation we think of as burdened with a hidebound class system-children who are born poor have a better chance of moving up. When the studies were released, most reporters focused on the finding that African-Americans born to middle-class or upper middle-class families are earning slightly less, in inflation-adjusted dollars, than did their parents.

One of the studies indicates, in fact, that most of the financial gains white families have made in the past three decades can be attributed to the entry of white women into the labor force. This is much less true for African-Americans.

The picture that emerges from all the quintiles, correlations and percentages is of a nation in which, overall, "the current generation of adults is better off than the previous one", as one of the studies notes.

The median income of the families in the sample group was $55,600 in the late 1960s; their children's median family income was measured at $71,900. However, this rising tide has not lifted all boats equally. The rich have seen far greater income gains than have the poor.

Even more troubling is that our nation of America as the land of opportunity gets little support from the data. Americans move fairly easily up and down the middle rungs of the ladder, but there is "stickiness at the ends" —four out of ten children who are born poor will remain poor, and four out often who are born rich will stay rich.

小题1:What did the Economic Mobility Project find in its research?

A．Children from low-income families are unable to bootstrap their way to the top.

B．Hollywood actors and actresses are upwardly mobile from rags to riches.

C．The rags to riches story is more fiction than reality.

D．The rags to riches story is only true for a small minority of whites.小题2:It can be inferred from the undertone of the writer that America, as a classless society, should ________.

A．perfect its self-image as a land of opportunity

B．have a higher level of upward mobility than Britain

C．enable African-Americans to have exclusive access to well-paid employment

D．encourage the current generation to work as hard as the previous generation小题3:Which of the following statements is TRUE according to the passage?

A．The US is a land where brains, energy and ambition are what counts.

B．Inequality persists between whites and blacks in financial gains.

C．Middle-class families earn slightly less with inflation considered.

D．Children in lowest-income families manage to climb a single rung of the ladder.小题4:What might be the best title for this passage?

A．Social Upward Mobility.

B．Incredible Income Gains.

C．Inequality in Wealth.

D．America Not Land of Opportunity.

( )表示同一对象不同时间之间的对比。

A．比较相对指标

B．结构相对指标

C．动态相对数

D．比例相对数

工程地质对建筑结构的影响，主要是地质缺陷和( )造成的。

A．岩层破碎
B．地下水
C．裂隙发育
D．活动断层

Will We Run Out of Water

Picture a "ghost ship" sinking into the sand, left to rot on dry land by a receding sea. Then imagine dust storms sweeping up toxic pesticides and chemical fertilizers from the dry seabed and spewing them across towns and villages.
Seem like a scene from a movie about the end of the world For people living near the Aral sea (咸海) in Central Asia, it’s all too real. Thirty years ago, government planners diverted the rivers that flow into the sea in order to irrigate (provide water for)farmland. As a result, the sea has shrunk to half its original size, stranding (使搁浅) ships on dry land. The seawater has tripled in salt content and become polluted, killing all 24 native species of fish.
Similar large-scale efforts to redirect water in other parts of the world have also ended in ecological crisis, according to numerous environmental groups. But many countries continue to build massive dams and irrigation systems, even though such projects can create more problems than they fix. Why People in many parts of the world are desperate for water, and more people will need more water in the next century.
"Growing populations wilt worsen problems with water," says Peter H. Gleick, an environmental scientist at the Pacific Institute for studies in Development, Environment, and Security, a research organization in California. He fears that by the year 2025, as many as one-third of the world’s projected (预测的) 8.3 billion people will suffer from water shortages.

WHERE WATER GOES

Only 2.5 percent of all water on Earth is freshwater, water suitable for drinking and growing food, says Sandra Postel, director of the Global Water Policy Project in Amherst, Mass. Two-thirds of this freshwater is locked in glaciers (冰山) and ice caps (冰盖). In fact, only a tiny percentage of freshwater is part of the water cycle, in which water evaporates and rises into the atmosphere, then condenses and falls back to Earth as precipitation (rain or snow).
Some precipitation runs off land to lakes and oceans, and some becomes groundwater, water that seeps into the earth. Much of this renewable freshwater ends up in remote places like the Amazon river basin in Brazil, where few people live. In fact, the world’s population has access to only 12,500 cubic kilometers of freshwater—about the amount of water in Lake Superior (苏必利尔湖). And people use half of this amount already. "If water demand continues to climb rapidly," says Postel, "there will be severe shortages and damage to the aquatic (水) environment."

CLOSE TO HOME

Water woes(灾难) may seem remote to people living in rich countries like the United States. But Americans could face serious water shortages, too especially in areas that rely on groundwater. Groundwater accumulates in aquifers (地下蓄水层), layers of sand and gravel that lie between soil and bedrock. (For every liter of surface water, more than 90 liters are hidden underground. )Although the United States has large aquifers, farmers, ranchers, and cities are tapping many of them for water faster than nature can replenish(补充) it. In northwest Texas, for example, overpumping has shrunk groundwater supplies by 25 percent, according to Postel.
Americans may face even more urgent problems from pollution. Drinking water in the United States is generally safe and meets high standards. Nevertheless, one in five Americans every day unknowingly drinks tap water contaminated with bacteria and chemical wastes, according to the Environmental Protection Agency. In Milwaukee, 400,000 people fell ill in 1993 after drinking tap water tainted with cryptosporidium (隐孢子虫), a microbe (微生物) that causes fever, diarrhea (腹泻) and vomiting.

THE SOURCE

Where do contaminants come from In developing countries, people dump raw (未经处理的) sewage(污水) into the same streams and rivers from which they draw water for drinking and cooking; about 250 million people a year get sick from water borne (饮水传染的) diseases.
In developed countries, manufactures use 100,000 chemical compounds to make a wide range of products. Toxic chemicals pollute water when released untreated into rivers and lakes. (Certain compounds, such as polychlorinated biphenyls (多氯化联二苯) ,or PCBs, have been banned in the United States.)
But almost everyone contributes to water pollution. People often pour household cleaners, car anti- freeze, and paint thinners (稀释剂) down the drain; all of these contain hazardous chemicals. Scientists studying water in the San Francisco Bay reported in 1996 that 70 percent of the pollutants could be traced to household waste.
Farmers have been criticized for overusing herbicides and pesticides, chemicals that kill weeds and insects but that pollute water as well. Farmers also use nitrates, nitrogen-rich fertilizer that helps plants grow but that can wreak havoc (大破坏) on the environment. Nitrates are swept away by surface runoff to lakes and seas. Too many nitrates "over enrich" these bodies of water, encouraging the buildup of algae, or microscopic plants that live on the surface of the water. Algae deprive the water of oxygen that fish need to survive, at times choking off life in an entire body of water.

WHAT’S THE SOLUTION

Water expert Gleick advocates conservation and local solutions to water-related problems; governments, for instance, would be better off building small-scale dams rather than huge and disruptive projects like the one that ruined the Aral Sea.
"More than 1 billion people worldwide don’t have access to basic clean drinking water," says Gleick, "There has to be a p push on the part of everyone—governments and ordinary people—to make sure we have a resource so fundamental to life.\

People in developed countries often pour more household cleaners, car antifreeze, and paint thinners down the drain than those in developing countries.