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Directions: Read the passage carefully. Then answer the questions or complete the statements in NO MORE THAN 25 WORDS.

As skies fill with millions of migrating birds, European scientists say the seasonal miracle appears to depend on a seeming contradiction: The fatter the bird, the more efficiently it flies. The results of their study contradict a central theory of aerodynamics（空氣動(dòng)力學(xué)）, which predicts that the power needed to fly increases with weight.

For birds, apparently, the cost of flying with heavy fuel loads is considerably smaller than previously thought. Researchers found that red knot wading birds double their normal body weight of 100 grams before making their twice-a-year, nonstop commute between the British Isles and the Russian Arctic. Distance: 5,000 kilometres.

Another study in the journal Nature measured the benefits of flying in an aerodynamic V formation, which allows birds to save energy by gliding in the lead bird’s air stream.

Flying in formation, their heart rates were as much as 14.5 per cent lower than flying solo, according to Henri Wimerskirch, a French scientist. The findings help explain how birds complete difficult migrations. Researchers had assumed that thinner, more athletic birds would have the best chance of survival.

The first study suggests that building up fat deposits to be burned as fuel during the migration is worth more than the energy it takes to carry the additional weight. Heavier birds apparently use their muscles more efficiently.

In the study, researchers said their team studied the birds flown at different body masses during 28 simulated flights. They were injected with a small amount of water containing a radioactive element that enabled the team to measure the amount of energy burned.

85. How much will a red knot wading bird probably weigh before making its nonstop migrating flight?

86. The additional weight gained before the flight won’t increase the powered needed to fly; on the contrary, it works as _____________________.

87. How did scientists successfully conduct the first study?

88. We can infer from the studies on fat deposits and V formation flying that both factors _____________________________.

Directions: Read the passage carefully. Then answer the questions or complete the statements in NO MORE THAN 25 WORDS.

As skies fill with millions of migrating birds, European scientists say the seasonal miracle appears to depend on a seeming contradiction: The fatter the bird, the more efficiently it flies. The results of their study contradict a central theory of aerodynamics（空氣動(dòng)力學(xué)）, which predicts that the power needed to fly increases with weight.

For birds, apparently, the cost of flying with heavy fuel loads is considerably smaller than previously thought. Researchers found that red knot wading birds double their normal body weight of 100 grams before making their twice-a-year, nonstop commute between the British Isles and the Russian Arctic. Distance: 5,000 kilometres.

Another study in the journal Nature measured the benefits of flying in an aerodynamic V formation, which allows birds to save energy by gliding in the lead bird’s air stream.

Flying in formation, their heart rates were as much as 14.5 per cent lower than flying solo, according to Henri Wimerskirch, a French scientist. The findings help explain how birds complete difficult migrations. Researchers had assumed that thinner, more athletic birds would have the best chance of survival.

The first study suggests that building up fat deposits to be burned as fuel during the migration is worth more than the energy it takes to carry the additional weight. Heavier birds apparently use their muscles more efficiently.

In the study, researchers said their team studied the birds flown at different body masses during 28 simulated flights. They were injected with a small amount of water containing a radioactive element that enabled the team to measure the amount of energy burned.

85. How much will a red knot wading bird probably weigh before making its nonstop migrating flight?

86. The additional weight gained before the flight won’t increase the powered needed to fly; on the contrary, it works as _____________________.

87. How did scientists successfully conduct the first study?

88. We can infer from the studies on fat deposits and V formation flying that both factors _____________________________.

Section D:

Directions: Read the passage carefully. Then answer the questions or complete the statements in NO MORE THAN 25 WORDS.

  As skies fill with millions of migrating birds, European scientists say the seasonal miracle appears to depend on a seeming contradiction: The fatter the bird, the more efficiently it flies. The results of their study contradict a central theory of aerodynamics（空氣動(dòng)力學(xué)）, which predicts that the power needed to fly increases with weight.

  For birds, apparently, the cost of flying with heavy fuel loads is considerably smaller than previously thought. Researchers found that red knot wading birds double their normal body weight of 100 grams before making their twice-a-year, nonstop commute between the British Isles and the Russian Arctic. Distance: 5,000 kilometres.

  Another study in the journal Nature measured the benefits of flying in an aerodynamic V formation, which allows birds to save energy by gliding in the lead bird’s air stream.

  Flying in formation, their heart rates were as much as 14.5 per cent lower than flying solo, according to Henri Wimerskirch, a French scientist. The findings help explain how birds complete difficult migrations. Researchers had assumed that thinner, more athletic birds would have the best chance of survival.

  The first study suggests that building up fat deposits to be burned as fuel during the migration is worth more than the energy it takes to carry the additional weight. Heavier birds apparently use their muscles more efficiently.

  In the study, researchers said their team studied the birds flown at different body masses during 28 simulated flights. They were injected with a small amount of water containing a radioactive element that enabled the team to measure the amount of energy burned.

How much will a red knot wading bird probably weigh before making its nonstop migrating flight?

_____________________________________________________________________________

86. The additional weight gained before the flight won’t increase the powered needed to fly; on the contrary, it works as _______________________________

87. How did scientists successfully conduct the first study?

___________________________________________________________________________________

88. We can infer from the studies on fat deposits and V formation flying that both factors _______________________________________________________________________________

閱讀理解

　　China's astronaut, 38-year-old Yang Liwei returned safely to earth Thursday morning, when his craft Shenzhou V touched down as scheduled after more than 21 hours in the earth's orbit. Chinese premier Wen Jiabao called the landmark debut flight a “complete success”. The descent capsule (返回艙) carrying Lt. Col. Yang Liwei touched down on the grasslands of the Gobi Desert, in central Inner Mongolia at 6:23 a. m. Thursday (Beijing Time), the Beijing-based China's Aerospace Command and Control Center said. Minutes later, Yang grabbed the capsule hatch with his hand, pulled himself out, smiled and waved at recovery teams and reporters. “It is a splendid moment in the history of my motherland and also the greatest day of my life,” Yang, a former flight pilot from Northeast China's Liaoning Province, said immediately after emerging. In an interview with CCTV, China's state television, Yang said he was “feeling excellent”. Shenzhou V landed at dawn, 4.8 kilometres (3 miles) from its designed landing target, the officials said. “The spaceship operated well,” the astronaut Yang Liwei said in his first publicized comments. “I feel very good and I am proud of my motherland.” After a physical exam on spot, Yang's condition was found as “good”. Li Jinai, the commander of China's manned space program, called Yang a “space hero” and a “national hero”. Following Yang's touchdown China's premier Wen Jiabao immediately spoke to Yang from Beijing's Command and Control Centre and offered his congratulations.

　　Within hours, Chinese space officials announced that the country's space dreams will continue with a “Shenzhou Ⅵ” mission, most possibly within a year. They said China also had worked out plans to conduct space walking by its astronauts, and eventually build up a space station. However, Chinese scientists ruled out building a space shuttle, like the United States.

　　Yang's flight came four decades after the former Soviet Union and the United States pioneered manned spaceflight. Soviet cosmonaut Yuri Gagarin orbited the Earth in April 1961. One month later, the United States launched Alan B. Shepard Jr.

1．What is true of the Chinese astronaut Yang Liwei?

[　　]

A．He is now a flight pilot.

B．He was helped to get out of the descent capsule.

C．He spent nearly a day in space.

D．He was called a “space hero” and a “national hero” by China's premier Wen Jiabao.

2．China will carry out the following space programs in the near future except ________.

[　　]

A．space walking

B．setting up a space station

C．building up a space shuttle

D．sending up “Shenzhou Ⅵ”

3．The underlined word debut means ________.

[　　]

4．Which of the following is NOT true?

[　　]

A．Soviet cosmonaut Yuri Gagarin was the first man in the world to travel in space.

B．The United States launched Alan B. Shepard Jr. about 43 years ago.

C．China is the third country in the world to carry out the manned space flight successfully.

D．“Shenzhou Ⅵ”will carry more than one astronaut in the mission.