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Like distance runners on a measured course, all of us will move through time in a roughly predictable pattern.
In the first stage of our lives, we develop and grow, reaching toward the top of physical vitality (活力,生气).
After we grow up, however, the body begins a process of gradually wearing out.
A new awareness of physical fitness may help lengthen our years of health and vitality, yet nothing we do will work to stop the unavoidable force of aging.
Most of the changes of aging take place deep inside the body. The lungs become less able to take in oxygen. Powerful muscles gradually lose their strength. The heart loses power and pumps less blood. Bones grow easier to break.
Finally, we meet a stress, a stress that is greater than our physical resistance. Often, it is only a minor accident or chance infection (a disease caused by virus), but this time, it brings life to an end.
In 1932, a classic experiment nearly doubled the lifetime of rats, simply by cutting back the calories in their diet. The reason for the effect was then unknown.
Today, at the University of California at Berkley, Dr. Paul Seagle has also greatly lengthened the normal lifetime of rats. The result was achieved through a special protein limited diet, which had a great effect on the chemistry of the brain. Seagle showed that within the brain, specific chemicals control many of the signals that influence aging. By changing that chemical balance, the clock of aging can be reset.
For the first time, the mystery of why we age is being seriously challenged. Scientists in many fields are now making striking and far-reaching discoveries.
An average lifetime lasts 75 years, yet in each of us lies a potential for a longer life. If we could keep the vitality and resistance to disease that we have at age twenty, we would live for 800 years.
What does the underlined word “it” refer to?

A.Physical vitality. B.Stress. C.Aging. D.Physical resistance.

Which of the following is not a change of aging?

A.The lungs become unable to take in oxygen.
B.People gradually lose their muscle strength.
C.The heart loses power and pumps less blood.
D.Bones tend to break more easily.

The author believes the following except that ________.

A.human’s life pattern is predictable
B.physical fitness can’t stop the force of aging
C.human’s lifetime will last longer than 75 years
D.all of the changes of aging take place deep inside the body

How did Dr. Paul Seagle lengthen the lifetime of rats in his experiment?

A.By limiting the protein in their diet. B.By cutting the calories in their diet.
C.By resetting their clock of aging. D.By keeping their physical fitness.

What is probably the best title for the article?

A.Two Great Experiments B.The Mystery of Human Life
C.Ways to lengthen Human Life D.The Breakthrough in the Study of Aging
科目 英语   题型 阅读理解   难度 中等
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Do you have a dream, something you always see yourself doing? Perhaps you see yourself as a lawyer, businessman, or even a scientist. Whatever it is, don’t let it die.
A dream is a wonderful thing. It can give you hope for your future and encourage you to try when all odds are against you.
However, there are dream killers that want to kill your dream. They may tell you that it is impossible for you, that you are not smart enough or that it’s never been done before. However, many times the biggest dream killer is yourself.
Don’t let fear, doubt or lack of finances prevent you from fulfilling(实现) your dream. Talk back to these killers, “I can and fulfill my dream.” You may have to do this every day. The more often you talk to your heart that you can do it, the more safely your dream will be held within you.
It is very important to take steps towards fulfilling your dream. For me, in order to fulfill my dream of one-day owning my own magazine, I needed to go back to school and finish my college degree. For you, it may be something different. You know deep inside what the voice of your dream calls for. Don’t be afraid and just do it. Try not to let too much time go by. Time is another one of those dream killers.
Think about the words of a song by Yolanda Adams, “Keep the dream alive. Don’t let it die. If something deep inside keeps inspiring you to try, don’t stop. And never give up. Don’t ever give up on you. Sometimes, life can place a stumbling block in your way. But you have to keep the faith.”
When you dream, dream big and never give up. Your dream is just yours. Never let anyone tell you that your dream can’t happen -- it can! Keep seeing yourself do what’s never been done before. As you continue to feed your dream and protect it, not only will you keep it alive, but it will come true.
What does the underlined words “all odds are against you” in Parragraph 2 mean?

A.You are in hopeless situation.
B.You find everything seems strange.
C.You are not feeling quite well.
D.You have all your friends against you.

What did the author dream of doing?

A.Getting his own book published B.Owing a colledge degree
C.Becoming a writer D.Publishing his own magazine

What do we learn from Paragraph 5?

A.It takes money to fulfill our dream.
B.The first step is to know our dream.
C.It is important for us to take action.
D.We should not listen to the call of our heart.

The words of Yolanda Adams’song are mentioned in the text.

A.to support his main point
B.to make his writing interesting
C.to show they share the same view
D.to mean Yolanda Adams is popular

When Callie Rogers won almost 1.9 million pounds on the lottery(彩票)at l6,she hoped it would help her put her troubles behind her.The teenager came from a broken home,had dropped out of school and was living in lotal authority care.
Rogers, from Cumbria, England, won the National Lottery in 2003. Then she went on a massive spending spree, splashing out on four homes for her family, flash cars, designer clothes, partying and breast implants. A fortnight after her win she married and had two children. But then she spent 250,000 pounds on cocaine and suffered depression. Earlier this year she lost custody of her children because of her mental state.
She became addicted to drugs and attempted suicide three times as her life unraveled. She says the money brought her only misery - and now she is down to her last 100,000 pounds, she has never been happier.
Now 22, she said: “Just a few months ago I was taking too many drugs and hated myself. I simply did not want to live any more. But now I have a new man and am finally becoming the woman I want to be.”
“I need to get my act together and make my kids proud, and for the first time I really do think that's possible.” She credits her new boyfriend with giving her the stable home life she has always craved, and she now hopes to go to college and eventually become a counselor. “After all I've endured, I think I have a lot of advice to offer,” she said.
Why was Rogers not allowed to look after her children?

A.She was in a bad mental state. B.Her children hated her.
C.She was not responsible for them. D.She was too poor to support them.

What can we learn about Rogers from Paragraph 3?

A.Being addicted to drugs cost her everything.
B.Money didn’t bring her happiness as expected.
C.Rogers felt sad with her money gone.
D.Too much money allowed her to do what she wanted.

What caused Rogers to change and start a new life?

A.The loss of money. B.Her bitter past.
C.Her husband and children. D.Her new boyfriend.

Thanksgiving Day is a special holiday in the United States and Canada.Families and friends gather to eat and give thanks for their blessing.
Thanksgiving Day is really a harvest festival.This is why it is celebrated in late fall,after the crops are in. But one of the first thanksgivings in America had nothing to do with a good harvest.On December 4,1619,the Pilgrims from England landed near what is now Charles City,Virginia.They knelt down and thanked God for their safe journey across the Atlantic.
The first New England Thanksgiving did celebrate a rich harvest.The Pilgrims landed at what is now Plymouth,Massachusetts,in 1620.They had a difficult time and the first winter was cruel.Many of the Pilgrims died. But the next year,they had a good harvest.So Governor Bradford declared a threeday feast (盛宴).The Pilgrims invited Indian friends to join them for their special feast. Everyone brought food.
In time,other colonies (殖民地) began to celebrate a day of thanksgiving. But it took years before there was a national Thanksgiving Day. During the Civil War,Sarah Josepha Hale persuaded Abraham Lincoln to do something about it. He proclaimed (宣布) the last Thursday of November 1863 as a day of thanksgiving. Today, Americans celebrate this happy harvest festival on the fourth Thursday in November.Canadians celebrate Thanksgiving Day in much the same way as their American neighbours.But the Canadian Thanksgiving Day falls on the second Monday in October.
Thanksgiving Day is celebrated .

A.in spring B.in summer
C.in autumn D.in winter

The first to celebrate thanksgiving were .

A.some people from England
B.the American Indians
C.Sarah Josepha Hale
D.Governor Bradford

We can infer from the passage that New England must be .
A.in the U.S.A.
B.in Great Britain
C.in Canada
D.on some island off the Atlantic
Which of the following is NOT true?

A.Thanksgiving Day used to be a holiday to celebrate a good harvest.
B.Abraham Lincoln was not the first to decide on thanksgiving celebrations.
C.Thanksgiving Day is celebrated to express the American and Indian people’s thanks to God.
D.There’s little difference between the American way and the Canadian way to celebrate Thanksgiving Day.

The passage mainly tells us .
A.how Thanksgiving Day is celebrated in the U.S.A.
B.how Thanksgiving Day came into being and the different ways it is celebrated
C.that Thanksgiving Day is in fact a harvest holiday
D.how the way to celebrate Thanksgiving Day changed with the time and places

Science has told us too much about the moon that it is fairly easy to imagine what it would be like to get there. It is certainly not a friendly place. Since there is no air or water, there can be no life of any kind. There is not much variety of scenery either. For mile after mile there are only flat plains of dust with mountains around them. Above, the sun and stars shine in the black sky. If you step out of the mountain shadow, it means moving from the severe cold into intense (强烈的) heat. These extreme temperatures continually break rocks away from the surface of the mountains. The moon is also a very silent world, for sound waves can only travel through air. But beyond the broken horizon, you see a friendly sight. Our earth is shining more brightly than the stars. From this distance, it looks like an immense (巨大的) blue, green and brown ball.
The moon is an unfriendly place because .

A.there is no air, no water, no life, no scenery B.the sun and stars shine in the sky
C.temperature breaks rock away D.all of the above

Without , the moon is a silent world.

A.man B.air C.sound D.water

According to the passage we know that .

A.the earth looks like a colored ball
B.we can enjoy the scenery on the moon
C.every inch of the moon is very hot
D.the extreme temperature breaks rocks away from the surface of mountains

We can conclude(断定) that “continually” means .

A.sometimes B.always C.without break D.frequently

The best title for the passage is .

A.An Unfriendly and Friendly Place B.The Geography of the Moon
C.Moon, a Silent World D.The Moon

“Mark Twain” was the name used by Samuel Langhorne Clemens (1835~1910) when he wrote books.His father was a lawyer,but a poor one,who lived in Florida,Missouri.The family was so poor that Samuel did not receive much teaching.He had to learn all that he could from the people whom he met.His father died when he was very young,and then there was even less money than before.
Many of the men in this part of America worked in the ships on the great Mississippi River,and he did this himself at one time (1857).
Where did he find the name “Mark Twain”? It came from the great river itself.It was part of one of the cries used by men who worked in the ships.When a man called “By the mark twain!” he meant that the river was “two marks deep” there,that is to say,six feet deep ( “Twain” is an old form of the word “Two”.) Samuel Clemens often heard these words when he was young,and he used them as a pen name all his life.
During his work on the Mississippi he met travelers of all kinds,and this helped him a great deal when he started to write.But the number of travelers became smaller when war started in America in 1861.Many of the great ships on the river stopped work.Samuel left then and went to Nevada with his brother,who was at that time Governor of Nevada.There,near the town of Carson,Samuel became a gold miner,but he never made much money at the time.He soon saw that life in the gold mines was not for him.He also tried writing for the newspapers in Nevada,and this seemed more hopeful.He found that he could write.
He went to Europe in 1867 and visited France and Italy.In 1870 he married Olivia Langdon,and two years later he was spending nearly all his time writing.Among his books is his own story (1908).
He is now always known as Mark Twain,and many people do not even know that his family name was Clemens.He traveled in America and in England,and went to Oxford in 1907.He was one of the great American writers of the time,and could make his readers laugh—a thing which few writers can do.He died in 1910.
“Mark Twain” was .

A.a famous American writer
B.name of a book
C.a great river in America
D.a large ship

As a child,Samuel did not get much education because .

A.his father died too early
B.the family was very poor
C.he disliked school very much
D.he could learn what he liked from the people he met

What gave him a great deal when he started writing?

A.His poor childhood.
B.The Mississippi River.
C.All kinds of travelers he met.
D.His brother.

We can infer(推断)from the passage that .

A.Samuel loved writing from his early age
B.Samuel did not love writing at the beginning
C.his writings to the newspaper were successful
D.his brother encouraged him to write more

According to the writer of the passage,a good writer could .

A.write a lot for his readers
B.make a lot of money for his family
C.cause his readers to laugh
D.travel everywhere he wanted

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