Far from the land of Antarctica, a huge shelf of ice meets the ocean. At the underside of the shelf there lives a small fish, the Antarctic cod. For forty years scientists have been curious about that 题目和参考答案——青夏教育精英家教网—

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Far from the land of Antarctica, a huge shelf of ice meets the ocean. At the underside of the shelf there lives a small fish, the Antarctic cod.

For forty years scientists have been curious about that fish. How does it live where most fish would freeze to death? It must have some secret. The Antarctic is not a comfortable place to work and research has been slow. Now it seems we have an answer.

Research was begun by cutting holes in the ice and catching the fish. Scientists studied the fish’s blood and measured its freezing point.

The fish were taken from seawater that had a temperature of -1.88℃ and many tiny pieces of ice floating in it. The blood of the fish did not begin to freeze until its temperature was lowered to -2.05℃. That small difference is enough for the fish to live at the freezing temperature of the ice-salt mixture.

The scientists’ next research job was clear: Find out what in the fish’s blood kept it from freezing. Their search led to some really strange thing made up of a protein(蛋白质) never before seen in the blood of a fish. When it was removed, the blood froze at seawater temperature. When it was put back, the blood again had its antifreeze quality and a lowered freezing point.

Study showed that it is an unusual kind of protein. It has many small sugar molecules(分子) held in special positions within each big protein molecules. Because of its sugar content, it is called a glycoprotein. So it has come to be called the antifreeze fish glycoprotein, or AFGP.

49. What is the text mainly about?

A. The terrible conditions in the Antarctic. B. A special fish living in freezing waters.

C. The ice shelf around Antarctic. D. Protection of the Antarctic cod.

50. Why can the Antarctic cod live at the freezing temperature?

A. The seawater has a temperature of -1.88℃.

B. It loves to live in the ice-salt mixture.

C. A special protein keeps it from freezing.

D. Its blood has a temperature lower than -2.05℃.

51. What does the underlined word “it” in Paragraph 5 refer to?

A. A type of ice-salt mixture. B. A newly found protein.

C. Fish blood. D. Sugar molecule.

52. What does “glycol” in the underlined word “glycoprotein” in the last paragraph mean?

A. sugar B. ice C. blood D. molecule

【答案】

49-52 BCBA

【解析】略

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IS THERE LIFE ON EARTH?

There was great excitement on the planet of Venus(金星) this week. For the first time Venusian scientists managed to land a satellite on the planet Earth, and it has been sending back signals as well as photographs ever since.?

The satellite was directed into an area known as Manhattan (named after the great Venusian astronomer Prof. Manhattan, who first discovered it with his telescope 20 000 light years ago).Because of excellent weather conditions and extremely strong signals, Venusian scientists were able to get valuable information as to feasibility(可行性) of a manned flying saucer(飞碟) landing on Earth.A press conference was held at the Venus Institute of Technology.?

“We have come to the conclusion,based on last week's satellite landing,” Pro. Zog said,“that there is no life on the Earth.”?

“How do you know this?” the science reporter of the Venus Evening Star asked. ?

“For one thing, Earth's surface in the area of Manhattan is composed of solid concrete(混凝土)and nothing can grow there. For another, the atmosphere is filled with carbon monoxide(一氧化碳) and other deadly gases and nobody could possibly breathe this air and survive.”?

“What does this mean as far as our flying saucer program is concerned?”?

“We shall have to take our own oxygen with us, which means a much heavier flying saucer than we originally planned. ”

“Are there any other hazards that you discovered in your studies?”?

“Take a look at this photo. You see this dark cloud floating over the surface of Earth? We call this the Consolidated Edison Belt. We don't know what it is made of, but it could give us a lot of trouble and we shall have to make further tests before we send a Venus Being there.”?

“If what you say is true, won't this set back the flying saucer program several years?”?

“Yes, but we shall proceed as soon as the Grubstart gives us the added funds.”?

“Prof. Zog, why are we spending billions and billions of zilches to land a flying saucer on Earth when there is no life there?”?

“Because if we Venusians can learn to breathe in an Earth atmosphere, then we can live anywhere.”

During the week of great excitement the Venusian scientists succeeded in getting important information on whether they can_______.

A. land a satellite with Venus astronauts on Earth

B. make a first?rate flying saucer?

C. get a Earth Being to Venus

D. direct a flying saucer into Manhattan?

According to Prof.Zog,the Venusians will have to take their own oxygen with them when they carry out their flying saucer program because_______.?

A. they need it on their way to the planet of Earth?

B. the Earth's atmosphere is filled with deadly gases?

C. oxygen is far from enough in the area of Manhattan where the saucer is to land?

D. there is no air on the planet of Earth?

The “dark black cloud” on the photograph refers to_______.?

A. the polluted air floating over the surface of Earth?

B. the mass of tiny drops of water floating above Earth?

C. the things that are unknown to everybody?

D. the dark clouds gathering before a storm breaks?

The author wishes to call our attention to the fact_______.?

A. that modern man has polluted his environment to such an extent that he might destroy himself if he went on like this?

B. that there is no point in spending billions and billions of zilches to land a flying saucer on Earth?

C. that pollution has become so serious a problem on Earth that even Venusians find life there unbearable?

D. that it is difficult, if not altogether impossible, to land a manned flying saucer on Earth

Ruben lived in a small village. There was no school there and he had to study in a school in the town. It was nearly five kilometres away from his village. His father couldn't buy a bike for him and he had to go to school on foot. He got up early in the morning. Usually he had to run there in order not to miss the first class. He kept running every day and it was helpful to him. He's strong and tall now and he ran faster than any other man in his village. He took part in several sports meetings and won some medals. The young man is proud of（以……自豪）it and always wants to have a race with others.

One day his mother was ill and his father told him to buy some medicine for headache in the town. The young man got there soon. There were many people in the chemist's shop while he was waiting there. And when his turn came, he could't find his money. An old woman hinted（暗示）a young man had stolen it. He saw the thief had already left the shop. He ran towards him quickly. The thief found it and began to run. He was happy and tried to catch up with him.

“Let's have a race and see who will run faster, ”Ruben called out behind.

Soon after that he caught up with the thief. But he didn't stop and went on running. At a crossing one of his friends asked, “What are you running for, Ruben? ”

“I'm running after（追）a thief. ”

“Where's the thief, then? ”

“He wants to show that he'll run faster than me, but he's fallen behind!”

59. Ruben had to run to school because ____.

A. he had no bike B. he hoped to win some medals

C. his village was a little far from the school D. he was afraid to be late for class

60. ____ , so he won some medals.

A. Ruben is good at running B. Ruben went to school on time

C. Ruben often took part in the sports meetings. D. Ruben likes to have a race with others

61. The phrase “a chemist's shop”in the story means ____.

A. 化工商店 B. 药店 C. 化工厂 D. 制药厂

62. Ruben's money was stolen ____.

A. on his way to the town B. before he went in the shop

C. when he was waiting in the shop D. after he had left the shop

63. Ruben was happy because ____.

A. he could easily catch the thief B. he had a chance（机会）to have a race

C. he knew who had stolen his money D. he would win another medal that day

Swimming is one of those activities that can be learned early in life. Little children can learn to swim as soon as they walk. In fact, you need the same skills in walking as in swimming. However, I believe that five is the best age to learn. By five or six, a child knows fear of water, a very important thing to know. It’s wise to be afraid, to recognize true danger. Young ones understand that the water can sometimes be very dangerous.

To really benefit from swimming, every swimmer should learn ; butterfly, backstroke, breaststroke, and crawl. I feel that one of these — the breaststroke — is different from the others, since some young swimmers use this stroke naturally, without any training.

In swimming, there are certain rules every swimmer should follow:

(1) Never swim alone! No matter how good you are in the water, don’t risk drowning by swimming alone. If you swim by yourself, with no life guards or friends with you, you may get into trouble.

(2) Don’t go beyond your abilities. Most swimmers know enough not to swim too far from the bank or the beach. Showing off by doing dangerous tricks is no good. Swim safely and you will continue to swim and alive.

(3) Don’t smoke .Swimming depends on a healthy body; good lungs are part of it.

(4) Work at any activity that builds muscles.

1.What is the main idea of the passage? (no more than 10 words)

2.Which age is best for a child to learn swimming? ( no more than 2 words )

3.Fill in the blank in Paragraph 2 with proper words. ( no more than 7 words )

4.Why can’t you swim alone according to the passage? ( no more than 10 words)

5.What does the underlined word “it” probably refer to? ( no more than 3 words )

The campaign is over. The celebrations have ended. And the work for US president-elect Barack Obama has begun.

The 47-year-old politician rose to the highest post because of his stand against the war in Iraq and his plans to fix a weak economy. But what will the first 47-year-old African-American president do for race relations.

Obama’s victory appears to have given blacks and other minorities a true national role model. For years, many looked to athletes and musicians for inspiration. As Darius Turner, an African-American high school student in Los Angeles, told the Los Angeles Times.“Kobe( the basketball player) doesn’t have to be everybody’s role model anymore.”

Recent polls also suggest that Obama’s victory has given Americans new optimism about race relations. For example, a USA Today poll found that two-thirds of Americans believe relations between blacks and whites“will finally be worked out”. This is the most hopeful response since the question was first asked during the civil rights revolution in 1963.

However, it’s still too early to tell whether Obama’s presidency will begin to solve many of the social problems facing low-income black communities.

Although blacks make up only 13 percent of the US population, 55 percent of all prisoners are African-American. Such numbers can be blamed on any number of factors on America’s racist past, a failure of government policy and the collapse of the family unit in black communities.

It is unlikely that Obama will be able to reverse（扭转）such trends overnight. However, Bill Bank, an expert of African-American Studies, say that eventually young blacks need to find role models in their own communities.“That’s not Martin Luther King, and not Barack Obama,”he told the Los Angeles Times, “It’s actually the people closest to them. Barack only has so much influence.”

In the opinion of black British politician Trevor Phillips, Obama’s rise will contribute more to multiculturalism than to race relations in the US.

52: For years, before Obama was elected president of the US, .

A. Kobe was the only role model for all the blacks

B. blacks could only find role models on the basketball court

C. minorities in America couldn’t find role models in their real life

D. American blacks had no role model who was successful in political area

53. According to Bill Bank, .

A. Obama is not the proper role model for African-Americans

B. young blacks should not be so much influenced by Obama

C. blacks should find other role models because Obama is far from their reality

D. it’s better for young blacks to find role models in those who are close to them

54. What do you think the author is probably going to talk about in the next paragraph?

A. In what ways Obama will contribute to racial relations in the US.

B. How Obama will influence Americans as a national role model.

C. How Obama will contribute to multiculturalism in the US.

D. How to choose a role model in his community as a young black.

55.What would be the best title for this passage?

A. The First African-American President

B. America’s New Role Model

C. Obama—a Successful Black

D. Choosing a Right Role Model

—Aren’t you cold?

—____．I’m boiling．

A．Take it easy．

B．That’s all right．

C．Not a little．

D．Far from it．

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