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科目: 来源:2013年普通高等学校招生全国统一考试(辽宁卷)英语 题型:050

阅读下列短文,从每题所给的四个选项(A、B、C、D)中,选出最佳选项。

  “Indeed, ” George Washington wrote in his diary in 1785, “some kind of fly, or bug, had begun to eat the leaves before I left home.” But the father of America was not the father of bug.When Washington wrote that, Englishmen hade been referring to insects as bugs for more than a century, and Americans had already created lightning-bug(萤火虫).But the English were soon to stop using the bugs in their language, leaving it to the Americans to call a bug a bug in the nineteenth and twentieth centuries.

  The American bug could also be a person, referring to someone who was crazy about a particular activity.Although fan became the usual term, sports fans used to be called racing bugs, baseball bugs, and the like.

  Or the bug could be a small machine or object, for example, a bug-shaped car.The bug could also be a burglar alarm, from which comes the expression to bug, that is, “to install(安装)an alarm”.Now it means a small piece of equipment that people use for listening secretly to others’ conversation.Since the 1840s, to bug has long meant “to cheat”, and since the 1940s it has been annoying.

  We also know the bug as a flaw in a computer program or other design.That meaning dates back to the time of Thomas Edison.In 1878 he explained bugs as “little problems and difficulties” that required months of study and labor to overcome in developing a successful product.In 1889 it was recorded that Edison “had been up the two previous nights discovering ‘a bug’ in his invented record player.”

(1)

We learn from Paragraph 1 that ________.

[  ]

A.

Americans had difficulty in learning to use the word bug

B.

George Washington was the first person to call an insect a bug

C.

the word bug was still popularly used in English in the nineteenth century

D.

both Englishman and Americans used the word bug in the eighteenth century

(2)

What does the word “flaw” in the last paragraph probably mean?

[  ]

A.

Explanation.

B.

Finding.

C.

Origin.

D.

Fault.

(3)

The passage is mainly concerned with ________.

[  ]

A.

the misunderstanding of the word bug

B.

the development of the word bug

C.

the public views of the word bug

D.

the special characteristics of the word bug

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科目: 来源:2013年普通高等学校招生全国统一考试(辽宁卷)英语 题型:050

阅读下列短文,从每题所给的四个选项(A、B、C、D)中,选出最佳选项。

  Here is an astonishing and significant fact: Mental work alone can't make us tire.It sounds absurd.But a years ago, scientists tried to find out how long the human brain could labor without reaching a stage of fatigue(疲劳).To the amazement of these scientists, they discovered that blood passing through the brain, when it is active, shows no fatigue at all! If we took a drop of blood from a day laborer, we would find it full of fatigue toxins(毒素)and fatigue products.But if we took blood from the brain of an Albert Einstein, it would show no fatigue toxins at the end of the day.

  So far as the brain is concerned, it can work as well and swiftly at the end of eight or even twelve hours of effort as at the beginning.The brain is totally tireless.So what makes us tired?

  Some scientists declare that most of our fatigue comes from our mental and emotional(情绪的)attitudes.One of England's most outstanding scientists, J.A.Hadfield, says, “The greater part of the fatigue from which we suffer is of mental origin.In fact, fatigue of purely physical origin is rare.” Dr.Brill, a famous American scientist, goes even further.He declares, “One hundred percent of the fatigue of sitting worker in good health is due to emotional problems.”

  What kinds of emotions make sitting workers tired? Joy? Satisfaction? No! A feeling of being bored, anger, anxiety, tenseness, worry, a feeling of not being appreciated-those are the emotions that tire sitting workers.Hard work by itself seldom causes fatigue.We get tired because our emotions produce nervousness in the body.

(1)

What surprised the scientists a few years ago?

[  ]

A.

Fatigue toxins could hardly be found in a laborer's blood.

B.

Albert Einstein didn't feel worn after a day's work.

C.

The brain could work for many hours without fatigue.

D.

A mental worker's blood was filled with fatigue toxins.

(2)

According to the author, which of the following can make sitting workers tired?

[  ]

A.

Challenging mental work.

B.

Unpleasant emotions.

C.

Endless tasks.

D.

Physical labor.

(3)

What's the author's attitude towards the scientists’ idea?

[  ]

A.

He agrees with them.

B.

He doubts them.

C.

He argues against them.

D.

He hesitates to accept them.

(4)

We can infer from the passage that in order to stay energetic, sitting workers need to ________.

[  ]

A.

have some good food.

B.

enjoy their work

C.

exercise regularly

D.

discover fatigue toxins

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科目: 来源:2013年普通高等学校招生全国统一考试(辽宁卷)英语 题型:050

阅读下列短文,从每题所给的四个选项(A、B、C、D)中,选出最佳选项。

  Going green seems to be fad(时尚)for a lot of people these days.Whether that is good or bad, we can't really say, but for the tow of us, going green is not a fad but a lifestyle.

  On April22, 2011, we decided to go green every single day for an entire year.This meant doing 365 different green things, and it also meant challenging ourselves to go green beyond easy things.Rather than recycle and reduce our energy, we had to think of 365 different green things to do and this was no easy task.

  With the idea of going green every single day for a year, Our Green Year started.My life and I decided to educate people about how they could go green in their lives and hoped we could show people all the green things that could be done to help the environment.We wanted to push the message that every little bit helps.

  Over the course of Our Green Year, we completely changed our lifestyle.We now shop at organic(有机的)stores.We consume less meat, choosing green food.We have greatly reduced our buying we don't need.We have given away half of what we owned through websites.Our home is kept clean by vinegar and lemon juice, with no chemical cleaners.We make our own butter, enjoying the smell of home-made fresh bread.In our home office anyone caught doing something ungreen might be punished.

  Our minds have been changed by Our Green Year.We are grateful for the chance to have been able to go green and educate others.We believe that we do have the power to change things and help our planet.

(1)

What might be the best title for the passage?

[  ]

A.

Going Green.

B.

Protecting the Planet.

C.

Keeping Open-Minded

D.

Celebrating Our Green Year.

(2)

It was difficult for the couple to live a green life for the whole year because ________.

[  ]

A.

they were expected to follow the green fad

B.

they didn't know how to educate other people

C.

they were unwilling to reduce their energy

D.

they needed to perform unusual green tasks

(3)

What did the couple do over the course of Our Green Year?

[  ]

A.

They tried to get out of their ungreen habits.

B.

They ignore others’ ungreen behavior.

C.

They chose better chemical cleaners.

D.

They sold their home-made food.

(4)

What can we infer form the last paragraph?

[  ]

A.

The government will give support to the green people.

B.

The couple may continue their project in the future.

C.

Some people disagree with the couple's green ideas.

D.

Our Green Year is becoming a national campaign.

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科目: 来源:2013年普通高等学校招生全国统一考试(辽宁卷)英语 题型:050

阅读下列短文,从每题所给的四个选项(A、B、C、D)中,选出最佳选项。

  China is a land of bicycles.At least it was back in 1992 when I traveled the country.Back then everyone seemed to be riding a bicycle.Millions of them, all black.Cars were rare.Yet since my arrival in Beijing last year, I’ve found the opposite is true.There are millions of cars.However, people still use their bicycles to get around.For many, it's the easiest and cheapest way to travel today.Bicycles also come in different colors-sivler, green, red, blue, yellow, whatever you want.

  It's fun watching people biking.They rush quickly through crossroads, move skillfully through traffic, and ride even on sidewalks(人行道).Bicycles allow people the freedom to move about that cars just can't provide.

  Eager to be part of this aspect of Chinese culture, I decided to buy a bicycle.Great weather accompanied my great buy.I immediately jumped up on my bicycle seat and started home.

  My first ride home was orderly(守秩序的).To be safe, I stayed with a “pack” of bikers while cars on the streets came running swiftly out of nowhere at times.I didn't want to get hit.So I took the ride carefully.

  Crossing the streets was the biggest problem.It was a lot like crossing a major highway back in the United States.The streets here were wide, so crossing took time, skill and a little bit of luck.

  I finally made it home.The feeling on the bicycle was amazing.The air hitting my face and going through my hair was wonderful.I was sitting on top of the world as I passed by places and people.Biking made me feel alive.

(1)

According to the author, why are bicycles still popular in China today?

[  ]

A.

Because they are traditional and safe.

B.

Because they are convenient and inexpensive.

C.

Because they are colorful and available.

D.

Because they are fast and environment friendly.

(2)

The author decided to buy a bicycle because he intended ________.

[  ]

A.

to ride it for fun

B.

to use it for transport

C.

to experience local skills

D.

to improve his riding skills

(3)

How did the author feel about his street crossing?

[  ]

A.

It was boring.

B.

It was difficult.

C.

It was lively.

D.

It was wonderful.

(4)

Which of the following best describes the author's biking experience?

[  ]

A.

The author enjoyed showing off his biking skills.

B.

The author was annoyed by the air while riding.

C.

The author was praised by the other bikers.

D.

The author took great pleasure in biking.

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科目: 来源:2013年普通高等学校招生全国统一考试(天津卷)英语 题型:050

阅读理解

  When asked about happiness, we usually think of something extraordinary, an absolute delight, which seems to get rarer the older we get.

  For kids, happiness has a magical quality.Their delight at winning a race or getting a new bike is unreserved(毫不掩饰的).

  In the teenage years the concept of happiness changes.Suddenly it's conditional on such things as excitement, love and popularity.I can still recall the excitement of being invited to dance with the most attractive boy at the school party.

  In adulthood the things that bring deep joy-love, marriage, birth-also bring responsibility and the risk of loss.For adults, happiness is complicated(复杂的)

  My definition fo happiness is “the capacity for enjoyment”.The more we can enjoy what we have, the happier we are.It's easy to overlook the pleasure we get from the company of friends, the freedom to live where we please, and even goo health.

  I experienced my little moments of pleasure yesterday.First I was overjoyed when I shut the last lunch-box and had the house to myself.Then I spent an uninterrupted morning writing, which I love.When the kids and my husband came home, I enjoyed their noise after the quiet of the day.

  Psychologists tell us that to be happy we need a mix of enjoyable leisure time and satisfying work.I don't think that my grandmother, who raised 14 children, had much of either.She did have a network of close friends and family, and maybe this is what satisfied her.

  We, however, with so many choices and such pressure to succeed in every area, have turned happiness into one more thing we’ve got to have.We’ve so self-conscious about our “right” to it that it's making us miserable.So we chase it and equal it with wealth and success, without noticing that the people who have those things aren't necessarily happier

  Happiness isn't about what happens to us-it's about how we see what happens to us.It's the skillful way of finding a positive for every negative.It's not wishing for what we don't have, but enjoying what we do possess.

(1)

As people grow older, they

[  ]

A.

feel it harder to experience happiness

B.

associate their happiness less with others

C.

will take fewer risks in pursuing happiness

D.

tend to believe responsibility means happiness

(2)

What can we learn about the author from Paragraph 5 and 6?

[  ]

A.

She cares little about her own health

B.

She enjoys the freedom of traveling

C.

She is easily pleased by things in daily life

D.

She prefers getting pleasure from housework

(3)

What can b informed from Paragraph 7?

[  ]

A.

Psychologists think satisfying work is key to happiness

B.

Psychologists’opinion is well proved by Grandma’case

C.

Grandma often found time for social gatherings

D.

Grandma's happiness came from modest expectations of life

(4)

People who equal happiness with wealth and success

[  ]

A.

consider pressure something blocking their way

B.

stress then right to happiness too much

C.

are at a loss to make correct choices

D.

are more likely to be happy

(5)

What can be concluded from the passage?

[  ]

A.

Happiness lies between the positive and the negative

B.

Each man is the master of his own fate

C.

Success leads to happiness

D.

Happy is he who is content

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科目: 来源:2013年普通高等学校招生全国统一考试(天津卷)英语 题型:050

阅读理解

  Poet William Stafford once said that we are defined more by the detours(绕行路)in life that by the narrow road toward goals.I like this image.But I as quite by accident that I discovered the deep meaning of his words.

  For years we made the long drive from our home in Seattle to my parents’ home in Boise in nine hours.We traveled the way most people do:the fastest, shortest easiest road, especially when ai was alone with four noisy, restless kids who hates confinement(限制)and have strong opinions about everything.

  Road trips felt risky, so I would drive fast, stopping only when I had to.We would stick to the freeways and arrive tired.

  But then Banner, our lamb was born.He was rejected by his mama days before our planned trip to Boise.I had two choices:leave Banner with my husband, or take him with me.My husband made the decision for me.

  That is how I found my self on the road with four kids, a baby lamb and nothing but my everlasting optimism to see me through.We took the country roads out of necessity.We had to stop every hour, let Banner shke out his legs and feed him.The kids chased him and one another.They'd get back in the car breathless and energized, smelling fresh from the cold air.

  We explored side roads, catching grasshoppers in waist-high grass.Even if we simply looked out of the car windows at baby pigs following their mother, or fish leaping out of the water, it was better than the best ride down the freeway.Here was life.And new horizons(见识).

  We eventually arrived at my parents'doorstep astonishingly fresh and full of stories

  I grew brave with the trip back home and creative with my disciplining technique.On an empty section of road, everyone started quarreling.I stopped the car, ordered all kids out and told them to meet me up ahead.I parked my car half a mile away and read my book in sweet silence.

  Some road trips are by necessity fast and straight.But that trip with Banner opened our eyes to a world available to anyon adventurous enough to wander around and made me realize that a detour may uncover the best part of a journey-and the best part of yourself.

(1)

Why did the author use to take freeways to her parents’home?

[  ]

A.

It was less time

B.

It would be faster and safer

C.

Her kids would feel less confined

D.

She felt better with other drivers nearby

(2)

The author stopped regularly on the country roads to

[  ]

A.

relax in the fresh air

B.

take a dep breath

C.

take care of the lamb

D.

let the kids play with Banner

(3)

What does the author discover from the trip according to Paragraph 6?

[  ]

A.

Freeways are where beauty hides.

B.

Getting close to nature adds to the joy of life

C.

Enjoying the beauty of nature benefits one's health

D.

One should follow side roads to watch wild animals

(4)

Why did the author ask the kids to get out of the car on their way back home?

[  ]

A.

To give herself some time to read

B.

To order some food for them

C.

To play a game with them.

D.

To let them cool down

(5)

What could be the best title for the passage?

[  ]

A.

Charm of the Detour

B.

The Road to Bravery

C.

Creativity out of Necessity

D.

Road trip and Country Life

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科目: 来源:2013年普通高等学校招生全国统一考试(天津卷)英语 题型:050

阅读理解

  Last night's meteor(流星)shower left many people in the community dissatisfied and demanding answers.According to Gabe Rothsclild, Emerald Valley's mayor, people gathered in the suburbs of the city, carrying heavy telescopes, expecting to watch the brightly burning meteors passing through the sky.What they found instead was a sky so brightened by the city's lights that it darkened the light of the meteors passing overhead.

  “My family was so frustrated, ” admitted town resident Duane Cosby, “We wanted to make this an unforgettable family outing, but it turned out to be a huge disappointments.”

  Astronomers-scientists who study stars and planets-have been complaining about this problem for decades.They say that light pollution prevents them from seeing objects in the sky that they could see quite easily in the past.They call on people and the government to take measures to fight against it.

  There is yet a population besides professional and amateur star observers that suffers even more from light pollution.This population consists of birds, bats frogs, snakes, etc.For example, outdoor lighting severely affects migrating(迁徙的)birds.According to the International Dark-Sky Association.“100 million birds a year throughout North America die in crashes with lighted buildings and towers.”

  Countless more animals casualties(伤亡)result from the use of artificial lighting.Clearly, people enjoy the benefits of lighting their evenings, but some scientists think it can be harmful for humans, too.They worry that exposure to light while sleeping can increase person's chances of getting cancer.

  Emerald Valley is only one community that is becoming aware of the negative effects of hight pollution.For years, Flagstaff, Arizona, has enforced lighting regulations in its city in order to assist astronomers at the Lowell Observatory.Similar efforts have been made worldwide, and a movement is underway to remind us to turn off lights when we are not using them, so that other creatures can share the night.

(1)

It happened last night that ________.

[  ]

A.

the city's lights affected the meteor watching

B.

the meteors flew past before being noticed

C.

the city light show attracted many people

D.

the meteor watching ended up a social outing

(2)

What do the astronomers complain about?

[  ]

A.

Meteor showers occur less often than before

B.

Their observation equipment is in poor repair

C.

Light pollution has remained unsolved for years

D.

Their eyesight is failing due to artificial lighting

(3)

What the author concerned about according to Paragraph 4?

[  ]

A.

Birds may take other migration paths

B.

Animal'living habits may change suddenly

C.

Varieties of animals will become sharply reduced

D.

Animals'survival is threatened by outdoor lighting

(4)

Lighting regulations in Flagstaff, Arizona are put into effect to

[  ]

A.

Lessen the chance of getting cancer

B.

create an ideal observation condition

C.

ensure citizens a good sleep at night

D.

enable all creatures to live in harmony

(5)

What message does the author most want to give us?

[  ]

A.

Saving wildlife is saving ourselves

B.

Great efforts should be made to save energy

C.

Human activities should be environmentally friendly

D.

New equipment should be introduced for space study

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科目: 来源:2013年普通高等学校招生全国统一考试(天津卷)英语 题型:050

阅读理解

Guide to Stockholm University Library

  Our library offers different types of studying places and provides a good studying environment.

  Zones

  The library is divided into different zones.The upper floor is a quiet zone with over a thousand places for silent reading, and places where you can sit and work with your own computer.The reading places consist mostly of tables and chairs.The ground floor is the zone where you can talk.Here you can find sofas and armchairs for group work.

  Computers

  You can use your own computer to connect to the wi-fi specially prepared for notebook computers, your can also use library computers, which contain the most commonly used applications, such as Microsoft Office.They are situated in the area known as the Experimental Field on the ground floor.

  Group-study places

  If you want to discuss freely without disturbing others, you can book a study room or sit at a table on the ground floor.Some study rooms are for 2-3 people and others can hold up to 6-8 people.All rooms are marked on the library maps.

  There are 40 group-study rooms that must be booked via the website.To book, you need an active University account and a valid University card.You can use a room three hours per day, nine hours at most per week.

  Storage of Study Material

  The library has lockers for students to store course literature, When you have obtained at least 40 credits(学分), you may rent a locker and pay 400 SEK for a year's rental period.

  Rules to be Followed

  Mobile phone conversations are not permitted anywhere in the librar.Keep your phone on silent as if you were in a lecture and exit the library if you need to receive calls.

  Please note that food and fruit are forbidden in the library, but you are allowed to have drinks and sweets with you.

(1)

The library's upper floor is mainly for students to ________.

[  ]

A.

read in a quiet place

B.

have group discussions

C.

take comfortable seats

D.

get their computers fixed

(2)

Library computers on the ground floor

[  ]

A.

help students with their field experiments

B.

contain software essential for schoolwork

C.

are for those who wan to access the wi-fi

D.

are mostly used for filling out application forms

(3)

What condition should be met to book a group-study room?

[  ]

A.

group must consist of 8 people

B.

Three-hour use per day is the minimum

C.

One should first register at the university

D.

Applicants must mark the room on the map

(4)

A student can rent a locker in the library if he

[  ]

A.

can afford the rental fee

B.

attends certain coursed

C.

has nowhere to put his books

D.

has earned the required credits

(5)

What should NOT be brought into the library?

[  ]

A.

Mobile phones

B.

Orange juice.

C.

Candy

D.

Sandwiches

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科目: 来源:2013年高考英语江苏卷 题型:050

请认真阅读下列短文,从短文后各题所给的A、B、C、D四个选项中,选出最佳选项。

  Mark Twain has been called the inventor of the American novel.And he surely deserves additional praise:the man who popularized the clever literary attack on racism.

  I say clever because anti-slavery fiction had been the important part of the literature in the years before the Civil War.H.B.Stowe's Uncle Tom's Cabin is only the most famous example.These early stories dealt directly with slavery.With minor exceptions, Twain planted his attacks on slavery and prejudice into tales that were on the surface about something else entirely.He drew his readers into the argument by drawing them into the story.

  Again and again, in the postwar years, Twain seemed forced to deal with the challenge of race.Consider the most controversial, at least today, of Twain's novels, Adventures of Huckleberry Finn.Only a few books have been kicked off the shelves as often as Huckleberry Finn, Twain's most widely read tale.Once upon a time, people hated the book because it struck them as rude.Twain himself wrote that those who banned the book considered the novel “trash and suitable only for the slums(贫民窟).” More recently the book has been attacked because of the character Jim, the escaped slave, and many occurences of the word nigger.(The term Nigger Jim, for which the novel is often severely criticized, never appears in it.)

  But the attacks were and are silly-and miss the point.The novel is strongly anti-slavery.Jim's search through the slave states for the family from whom he has been forcibly parted is heroic.As J.Chadwick has pointed out, the character of Jim was a first in American fiction-a recognition that the slave had two personalities, “the voice of survival within a white slave culture and the voice of the individual:Jim, the father and the man.”

  There is much more.Twain's mystery novel Pudd’nhead Wilson stood as a challenge to the racial beliefs of even many of the liberals of his day.Written at a time when the accepted wisdom held Negroes to be inferior(低等的)to whites, especially in intelligence, Twain's tale centered in part around two babies switched at birth.A slave gave birth to her master's baby and, for fear that the child should be sold South, switched him for the master's baby by his wife.The slave's lightskinned child was taken to be white and grew up with both the attitudes and the education of the slave-holding class.The master's wife's baby was taken for black and grew up with the attitudes and intonations of the slave.

  The point was difficult to miss:nurture(养育), not nature, was the key to social status.The features of the black man that provided the stuff of prejudice-manner of speech, for example-were, to Twain, indicative of nothing other than the conditioning that slavery forced on its victims.

  Twain's racial tone was not perfect.One is left uneasy, for example, by the lengthy passage in his autobiography(自传)about how much he loved what were called “nigger shows” in his youth-mostly with white men performing in black-face-and his delight in getting his mother to laugh at them.Yet there is no reason to think Twain saw the shows as representing reality.His frequent attacks on slavery and prejudice suggest his keen awareness that they did not.

  Was Twain a racist? Asking the question in the 21st century is as wise as asking the same of Lincoln.If we read the words and attitudes of the past through the “wisdom” of the considered moral judgments of the present, we will find nothing but error.Lincoln, who believed the black man the inferior of the white, fought and won a war to free him.And Twain, raised in a slave state, briefly a soldier, and inventor of Jim, may have done more to anger the nation over racial injustice and awaken its collective conscience than any other novelist in the past century.

(1)

How do Twain's novels on slavery differ from Stowe's?

[  ]

A.

Twain was more willing to deal with racism.

B.

Twain's attack on racism was much less open.

C.

Twain's themes seemed to agree with plots.

D.

Twain was openly concerned with racism.

(2)

Recent criticism of Adventures of Huckleberry Finn arose partly from its ________.

[  ]

A.

target readers at the bottom

B.

anti-slavery attitude

C.

rather impolite language

D.

frequent use of “nigger”

(3)

What best proves Twain's anti-slavery stand according to the author?

[  ]

A.

Jim's search for his family was described in detail.

B.

The slave's voice was first heard in American novels.

C.

Jim grew up into a man and a father in the white culture.

D.

Twain suspected that the slaves were less intelligent.

(4)

The story of two babies switched mainly indicates that ________.

[  ]

A.

slaves were forced to give up their babies to their masters

B.

slaves’ babies could pick up slave-holders’ way of speaking

C.

blacks’ social position was shaped by how they were brought up

D.

blacks were born with certain features of prejudice

(5)

What does the underlined word “they” in Paragraph 7 refer to?

[  ]

A.

The attacks.

B.

Slavery and prejudice.

C.

White men.

D.

The shows.

(6)

What does the author mainly argue for?

[  ]

A.

Twain had done more than his contemporary writers to attack racism.

B.

Twain was an admirable figure comparable to Abraham Lincoln.

C.

Twain's works had been banned on unreasonable grounds.

D.

Twain's works should be read from a historical point of view.

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科目: 来源:2013年高考英语江苏卷 题型:050

请认真阅读下列短文,从短文后各题所给的A、B、C、D四个选项中,选出最佳选项。

  If a diver surfaces too quickly, he may suffer the bends.Nitrogen(氮)dissolved(溶解)in his blood is suddenly liberated by the reduction of pressure.The consequence, if the bubbles(气泡)accumulate in a joint, is sharp pain and a bent body-thus the name.If the bubbles form in his lungs or his brain, the consequence can be death.

  Other air-breathing animals also suffer this decompression(减压)sickness if they surface too fast:whales, for example.And so, long ago, did ichthyosaurs.That these ancient sea animals got the bends can be seen from their bones.If bubbles of nitrogen form inside the bone they can cut off its blood supply.This kills the cells in the bone, and consequently weakens it, sometimes to the point of collapse.Fossil(化石)bones that have caved in on themselves are thus a sign that the animal once had the bends.

  Bruce Rothschild of the University of Kansas knew all this when he began a study of ichthyosaur bones to find out how widespread the problem was in the past.What he particularly wanted to investigate was how ichthyosaurs adapted to the problem of decompression over the 150 million years.To this end, he and his colleagues traveled the world's natural-history museums, looking at hundreds of ichthyosaurs from the Triassic period and from the later Jurassic and Cretaceous periods.

  When he started, he assumed that signs of the bends would be rarer in younger fossils, reflecting their gradual evolution of measures to deal with decompression.Instead, he was astonished to discover the opposite.More than 15% of Jurassic and Cretaceous ichthyosaurs had suffered the bends before they died, but not a single Triassic specimen(标本)showed evidence of that sort of injury.

  If ichthyosaurs did evolve an anti-decompression means, they clearly did so quickly-and, most strangely, they lost it afterwards.But that is not what Dr Rothschild thinks happened.He suspects it was evolution in other animals that caused the change.

  Whales that suffer the bends often do so because they have surfaced to escape a predator(捕食动物)such as a large shark.One of the features of Jurassic oceans was an abundance of large sharks and crocodiles, both of which were fond of ichthyosaur lunches.Triassic oceans, by contrast, were mercifully shark-and crocodile-free.In the Triassic, then, ichthyosaurs were top of the food chain.In the Jurassic and Cretaceous, they were prey(猎物)as well as predator-and often had to make a speedy exit as a result.

(1)

Which of the following is a typical symptom of the bends?

[  ]

A.

A twisted body.

B.

A gradual decrease in blood supply.

C.

A sudden release of nitrogen in blood.

D.

A drop in blood pressure.

(2)

The purpose of Rothschild's study is to see ________.

[  ]

A.

how often ichthyosaurs caught the bends

B.

how ichthyosaurs adapted to decompression

C.

why ichthyosaurs bent their bodies

D.

when ichthyosaurs broke their bones

(3)

Rothschild's finding stated in Paragraph 4 ________.

[  ]

A.

confirmed his assumption

B.

speeded up his research process

C.

disagreed with his assumption

D.

changed his research objectives

(4)

Rothschild might have concluded that ichthyosaurs ________.

[  ]

A.

failed to evolve an anti-decompression means

B.

gradually developed measures against the bends

C.

died out because of large sharks and crocodiles

D.

evolved an anti-decompression means but soon lost it

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