【推荐1】Natural lakes cover about 2.8% of Earth's non-oceanic surface. Despite the small percentage, they are very important to both regional and global ecosystems. However, lakes around the world, such as the Great Lakes in the United States, the Aral Sea and the Dead Sea in Asia and the Lake Chad in Africa, are disappearing and even have disappeared. Identifying the main factors of lakes' decline is of great value for global lake management and lake recovery, especially for the largest freshwater lake in China, Poyang Lake.

Located in eastern China's Jiangxi Province, Poyang Lake has a drainage(灌排) area of 162,225 km2，feeds a population of up to 44 million and annually supplies 17% of the water for the Yangtze River, the longest river in Asia and the third longest in the world. It also provides a home for millions of birds during the lake's low water stages in late autumn and winter, including 95% of the world's endangered white cranes. Moreover, the variations in the lake's water output directly affect the environments in the East China Sea.

However, since the beginning of the 21st century, Poyang Lake has experienced continuously extreme low water levels in autumn, which has put the threatened birds at risk of extinction.

Despite several efforts to explore the causes of the Poyang Lake's dryness, to date, there have been no studies that attempt to distinguish and quantify the contribution of each possible factor on the lake's recent low water levels.

Therefore, the objectives of my study are to quantify the contribution of each factor leading to Poyang Lake's dryness. These results are of vital value in characterizing the problems of the Poyang Lake and its related wetlands. They also can be applied to other large lakes in similar situations around the world.

1. What is the author's main purpose in the first paragraph?

A．To tell the necessity and value of his study.

B．To show the problems of the four largest lakes.

C．To introduce the lakes' coverage of the earth's surface.

D．To prove the lakes' importance to the global ecosystems.

2. What can be known about Poyang Lake?

A．It is the main water source for the Yangtze River.

B．It is the third biggest freshwater lake in the world.

C．It is home to 95% of the world's endangered animals.

D．It is important to the ecosystem of the East China Sea.

3. What does the author say about the previous studies?

A．Their theories about the lake are wrong.

B．They should carry out their study in quality.

C．They have not analyzed each factor in quantity.

D．Their studies cannot be applied to the other lakes.

4. Where is this text most likely from?

A．A textbook.	B．A newspaper.
C．A research paper.	D．An advertisement.

【推荐2】Biscayne is not very far from the lights, noise and excitement of downtown Miami. But it has a very different atmosphere from the big city. Biscayne National Park was established as a national monument in 1968. It became a national park in 1980. That year, its size also increased. The park now covers more than 70,000 hectares.

If you enjoy water, Biscayne is the park for you. Ninety-five percent of the park is water. Many kinds of animals live in these waters. Some of them are threatened or endangered. You will find the huge, gentle West Indian manatee, the less gentle American crocodile, several kinds of sea turtles, and more than 500 species of fish.

Scientists say Human history at Biscayne begins more than 10,000 years ago. However, evidence of the area’s earliest people is mostly underwater now, as water levels have risen over time. Within the last 3,000 years, people began to settle in the area. Scientists continue to learn about these people by examining the big hills of shells they left behind. The shells contain other waste, too, including early tools and house wares.

European explorers began arriving in the area in the early 1500s. They brought with them diseases like smallpox and measles. Over time, these diseases killed huge numbers of natives. Early explorers arrived in the area on ships. The reefs and rough waters made it difficult for ship captains. Biscayne’s waters contain more than 50 shipwrecks. Scuba divers today can explore six of them.

Four ecosystems come together here, which is what makes the park so diverse. The blending ecosystems create “edge communities.” These edge communities support a huge amount of wildlife. The underwater diversity is what attracts most people to Biscayne National Park. Many visitors come here to scuba dive in Biscayne’s clear and warm waters.

1. What happened to Biscayne National Park in 1980?

A．It began to be set up as a national park.	B．It was built as a national monument.
C．It became much larger in area.	D．It covered more than 70,000 hectares.

2. By examining the shells they left behind, scientists can ________.

A．learn about the sea animals	B．know how old the place is
C．learn when the earliest people arrived	D．learn about the life of the earliest people

3. Huge number of natives were killed ________.

A．on their voyage to Biscayne	B．by diseases brought by Europeans
C．in their fight against the Europeans	D．because of lack of proper food

4. What attracts tourists most to Biscayne National Park?

A．Its ecosystems.	B．Its long history.
C．Its underwater activities.	D．Its endangered animals.

【推荐3】Antarctica

Weather

Antarctica lies in the most southern part of the world. It is the coldest area on Earth. There isn’t much rain, but there is a lot of snow and wind. The lowest temperature was on 21 July in 1983 at -89.2℃!

Population

Nobody lives in Antarctica all the time! The first people to stay there for a while were fishermen in 1786. Now there are about 5,000 scientists and researchers there in the summer.

History of exploration (探险)

During 1907-1909, British explorer Earnest Shackleton explored Antarctica on foot. In 1911, two explorers — a British man named Scott and a Norwegian named Amundsen — raced 1,400 kilometers to the South Pole (南极). Amundsen arrived first.

Animals and birds

There aren’t any large animals in Antarctica. Polar bears live at the North Pole. But there are a lot of penguins and seabirds. Every spring there are over 100 million seabirds in Antarctica.

1. When did the lowest temperature appear in Antarctica?

A．In 1786.

B．In 1907.

C．In 1911.

D．In 1983.

2. Who first stayed in Antarctica for some time?

A．Fishermen.

B．Scientists.

C．Researchers.

D．Explorers.

3. Where is Earnest Shackleton from?

A．Britain.

B．Norway.

C．The South Pole.

D．The North Pole.