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Seven of America's Natural Wonders

Niagara Falls

The United States shares Niagara Falls with Canada. That thundering crash is the tens of thousands of cubic feet of water that flow each second over Niagara Falls which includes the American Falls and Horse- shoe Falls. The American Falls in New York State extends more than 320 meters across part of the Niagara River. The American Falls is more than 50 meters high.

Canada owns the larger Horseshoe Falls. It is about 800 meters wide and almost 50 meters high. It is shaped like the letter U, or a horse's shoe.

Niagara Falls formed about 12,000 years ago when huge melting sheets of ice formed the Great Lakes. The land was uneven with several drops in level, some very sharp. Water from Lake Erie began to flow north to Lake Ontario as a result of the loss of the ice barrier.

The Everglades(大沼泽)

The Everglades once called "the liquid heart" lies in the state of Florida.

Hundreds of birds fly in a sunny blue sky. The only sounds are bird calls and the soft noise made by tall grasses as the water slowly moves them. Hidden in the grasses, dark green alligators(美洲鳄)move at the edge of the water, like part of the Earth come alive.

This is the Everglades -- a low, watery, partly coastal area that covers 10,000 square kilometers. The area is filled with sawgrass. This plant grows in sharp, thin pieces that are 3 to 10 meters tall. The Everglades is sometimes called "river of grass."

The area also contains forests of palm, cypress(柏树), mangrove(红树林)and pine. And beautiful plants and sweet-smelling flowers grow in the Everglades. These include several kinds of the highly prized and rare flower, the orchid(兰花). Animal species are plentiful. Many colorful birds and butterflies live here. So do snakes, foxes, frogs and even big cats, called Florida panthers(黑豹). But, the Everglades alligators and crocodiles are probably the animals most identified with the Everglades. No other place in the world is home to both.

Badlands

In the state of South Dakota, the land is big and mostly flat with many fields of corn, wheat and soy-beans. But as the tourists traveling west, the cropland gives way to wild grasses. A strong dry wind blows continuously from the west.

Suddenly, the land becomes torn and rocky, dry and dusty -- no longer green and gold. It is now a light red-brown color. All around are broken disordered forms. There are hills and valleys of all sizes and strange shapes.

These are the Badlands. Hundreds of thousands of years ago the area was grassland. But, then, forces of nature destroyed the grass. Water and ice cut into the surface of the earth. They beat at the rocks, wearing them away. The result is one of the world's strangest sights.

All together, the Badlands cover more than 15,000 square kilometers. About 10 percent is national parkland. The area is a study in extremes. Temperatures in the summer have been as high as 46 degrees Celsius. In the winter they have dropped to as low as 41 degrees below zero. Life in the Badlands is difficult. But animals do survive. The most well known is the prairie dog. This small mammal lives in a series of underground passages.

The Grand Canyon

The Grand Canyon is a huge hole in the Earth in the state of Arizona. The first sight is breathtaking. The Grand Canyon stretches for hundreds of kilometers before us and hundreds of meters below us. It is about 24 kilometers across at its widest point. Its deepest point is almost 2,000 meters down.

The Grand Canyon is a series of deep long cuts in rock. There are many passages and large raised areas. There are forests on the top level and desert areas down below. They provide support for several different ecosystems. The Colorado River flows through the Grand Canyon. The Canyon offers a lot of information about

A．Y

B．N

C．NG

听力原文： The United Nations is predicting food shortages in Zimbabwe this year because of government policies that allowed war veterans to take over hundreds of white owned farms, crippling their production.

In a report published Friday, the U. N. Food and Agricultural Organization foresees a nearly one-quarter drop in Zim babwe’s cereal production from last year. This includes a plunge of more than 50 percent in corn yields. The report says Zimbabwe will probably need to import more than 500,000 tons of cereals this year, but has only the hard currency to purchase about one-fifth that amount.

The FAO study says the urban poor and low-income residents of southern and eastern Zimbabwe are most vulnerable to food shortages.

Zimbabwe President Robert Mugabe has described the seizure of farms as a justified protest against the ownership by whites of about a third of the country’s productive land.

The government wants to expropriate white-owned land without compensation and redistribute it to landless blacks.

According to the U. N. Food and Agricultural Organization, how much will Zimbabwe’s cereal production drop from last year?

A．25%.

B．15%.

C．50%.

D．20%.

听力原文： The United Nations is predicting food shortages in Zimbabwe this year because of government policies that al-lowed war veterans to take over hundreds of white owned farms, crippling their production.

In a report published Friday, the U.N. Food and Ag-ricultural Organization foresees a nearly one-quarter drop in Zimbabwe's cereal production from last year. This includes a plunge of more than 50 percent in corn yields. The report says Zimbabwe will probably need to import more than 500,000 tons of cereals this year, but has only the hard currency to purchase about one-fifth that a-mount.

The FAO study says the urban poor and low-income residents of southern and eastern Zimbabwe are most vulnerable to food shortages.

Zimbabwe President Robert Mugabe has described the seizure of farms as a justified protest against the ownership by whites of about a third of the country’s productive land.

The government wants to expropriate white-owned land without compensation and redistribute it to landless blacks.

According to the U.N. Food and Agricultural Organization, how much will Zimbabwe’s cereal production drop from last year?

A．25%.

B．15%.

C．50%.

D．20%.

Section A

A soaring dropout rate is causing the United States to lose ground educationally to rivals and is trapping millions of young Americans at the very margins of the economy.【76】The Obama administration acknowledges the problem in its new budget, which includes a $50 million prevention programme , but solving this problem will require a lot more money and a comprehensive national strategy.

The alarming scope of dropout crisis is laid out by the Centre for Labour Market Studies at Northeastern University in Boston and Alternative Schools Network in Chicago .【77】Their study, which examines data from the 12 largest states, finds that 16 percent of people from the ages of 16 to 24 have dropped out.

【78】The problem is especially pronounced among men, who make up more than 60 percent of those who change school nationally. The dropout problem hits minorities really hard.

【79】Many of this country’s large urban high schools are rightly called " dropout factories" because more students leave school than graduate. According to the study, state dropout rates are highest in the South, where Georgia (22.1 percent), Florida (20.1 percent) and Texas (18. 5 percent)lead the way.

【80】The dropout crisis presents a clear danger to national prosperity , but at the moment states and localities are struggling to contain it with little help or guidance from the federal government. Congress, which is just waking up to this issue, can improve the situation by putting its money and muscle behind proven programmes that have been shown to re-engage young people who have dropped out, and that keep at-risk children on track to complete their educations.

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