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.
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.

1. What does the underlined word "it" refer to?
A. Physical vitality.    
B. Stress.
C. Aging.
D. Physical resistance.

2. 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.

3. 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

4. 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.

5. 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
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相關(guān)習(xí)題

科目：高中英語 來源：廣東省期末題 題型：填空題

語法填空
閱讀下面短文，按照句子結(jié)構(gòu)的語法性和上下文連貫的要求，在空格處填入一個適當?shù)脑~或使用括號中詞語的正確形式填空，并將答案填寫在標號為1~10的相應(yīng)位置上。
     When China’s ancient scientific and technological achievements are mentioned, the nation will generally refer to the Four Great inventions. The four symbolic    1   (create) - compass, papermaking, printing and gunpowder --       2     pride of China’s 5,000-thousand-year-old culture, because of their    3    
(recognize) role in the development of human civilization.
          4    is therefore no surprise that the recent proposal by a group of scholars    5       (redefine) the
Four Great Invention has caused a heated reaction. According to the proposed new version, papermaking and printing    6      (merge) into one entry, and compass and gunpowder are delisted. The three new
inclusions are silk, bronze and porcelain,     7       proposers said could more scientifically exhibit the most
advanced and most influential scientific contributions of ancient China.
     The question of     8     the Four Great Invention should be is of course open to the debate. The   9    
(late) redefinition attempt, which is reported based on careful studies of available written records and
antiques, can at least help today’s people, the younger generation,     10    particular, know more about the brilliance of ancient Chinese civilization.

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科目：高中英語 來源：福建省月考題 題型：完形填空

完形填空
     Can you really make out the difference between British Isles, Britain, United Kingdom and England?
These terms are familiar to us, but meanwhile ____1_____to us Chinese.
     The British Isles are made up of two large ____2____: One is Britain and the other Ireland. Britain, or
Great Britain, is the ____3____of the two islands, which is ___ 4_____ into three parts: England, Scotland
and Wale.The United Kingdom (UK) is short for the United Kingdom of Great Britain and Northern
Ireland. UK ____5___ Scotland, Wales and England ( i.e. the whole of Britain), and also about one-sixth
of Ireland, the northern part. The ____6____ of Ireland called the Republic of Ireland is another country.
     England is the largest of the four, and generally speaking, the richest section. Its capital is London,
____7____ is also the capital of the UK. London lies on the River Thames. Much of England is rather flat,
although there are  ____8____ in the northeast and in the center of the country. English people tend to use
the ____9____ "England" and "English" when they mean "Britain" and "British". This sometimes upsets the Welsh and the Scots as they are not included. "Why don't they use 'Walsh' or '____10___' ?" they may
wonder.
     London is beautiful. Today, you cannot deny the beauty, myth, and wonder of the River Thames, which
has good ____11____. However,in the nineteenth century, in some books, the Thames was ____12____
as a grey, dirty, smutty, sooty, smoky river. These were not only existing in nineteenth century. It had
____13____ been like this for centuries,never clear.
     At that time, many ordinary people were ___14       to cholera. This was the ____15____ disease of its day. Neither its cause nor its cure was understood. No one knew the disease just came from the  
___16      water.
So many thousands of ___17___ people died every time there was an(a) ___18       . Disasters like these
always remain us unforgettable lessons.
     Now you know England is of course different from the UK. At present, the UK played an important part in the ____19____affairs. It is a member state of the United Nations, ____20____ the European Union and NATO. "The UN, the UK and the US often go hand in hand in the world,"  people joke. Do you think so?
(     )1. A. uninteresting
(     )2. A. lands      
(     )3. A. larger      
(     )4. A. separated  
(     )5. A. approves of
(     )6. A. part        
(     )7. A. it          
(     )8. A. hills      
(     )9. A. nouns      
(     )10. A. Scottish  
(     )11. A. appearance
(     )12. A. observed  
(     )13. A. sometimes  
(     )14. A. brought    
(     )15. A. enormous  
(     )16. A. waste      
(     )17. A. worried    
(     )18. A. outbreak  
(     )19. A. western    
(     )20. A. except for		 B. surprising  
B. islands    
B. largest    
B. divided    
B. disposes of
B. half        
B. that        
B. lakes      
B. words      
B. England    
B. tastes      
B. found      
B. often      
B. shown       
B. powerful    
B. clean      
B. wounded    
B. war        
B. European    
B. as well as   		C. puzzling    
C. continents  
C. smaller    
C. changed    
C. consists of
C. rest        
C. which      
C. rivers      
C. language    
C. Britain    
C. environment
C. thought    
C. almost      
C. led         
C. terrifying  
C. polluted    
C. cured      
C. fighting    
C. international
C. linking to   		D. amazing      
D. provinces    
D. smallest    
D. sent        
D. complains of
D. others      
D. who          
D. plains      
D. vocabulary  
D. English      
D. surroundings
D. described    
D. always      
D. exposed      
D. deadly      
D. pumped      
D. affected    
D. flood        
D. nationwide  
D. relating to  

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科目：高中英語 來源：福建省期中題 題型：閱讀理解

     Years ago, when I started looking for my first job, wise advisers said, "Barbara, be enthusiastic!
Enthusiasm will take you further than any amount of experience." How right they were!
     "Nothing great was ever achieved without enthusiasm," wrote Ralph Waldo Emerson. It is the paste
that helps you hang on there when the going gets tough. It is the inner voice that whispers, "I can do it!"
when others shout, "No, you can't!" It took years and years for the early work of Barbara Mc Clintock,
a geneticist (遺傳學(xué)家) who won the 1983 Nobel Prize in medicine, to be generally accepted. Yet she
didn't let up on (放松) her experiments. Work was such a deep pleasure for her that she never thought
of stopping.
     We are all born with wide-eyed, enthusiastic wonder and it is this childlike wonder that gives
enthusiastic people such youthful air, whatever their age. At 90, cellist (大提琴家) Pablo Casals would
start his day by playing Bach. As the music flowed through his fingers, his bent shoulders would
straighten and joy would reappear in his eyes. As author and poet Samuel once wrote, "Years make the
skin old, but to give up enthusiasm makes the soul old."
     Enthusiastic people also love what they do, regardless of money, title or power. Patricia Mcllrath,
retired director of the Missouri Repertory Theater in Kansas City, was once asked where she got her
enthusiasm. She replied, "My father, a lawyer, long ago told me, I never made a penny until I stopped
working for money."
     If we cannot do what we love as a fulltime career, we can do it as a hobby. Elizabeth Layton of
Wellsville, Kan, was 68 before she began to draw. This activity ended her sadness that had troubled her
for at least 30 years, and the quality of her work led one critic to say, "I am persuaded to call Layton a
genius."
     We can't afford to waste tears on "might-have-beens". We need to turn the tears into sweat as we go
after "what-can-be". We need to live each moment whole-heartedly, with all our senses — finding
pleasure in the sweet smell of a backyard garden, the simple picture of a six-year-old, and the beauty
of a rainbow.              
1. The passage mainly shows us ____.
A. enthusiasm leads to everything
B. we can do nothing without enthusiasm
C. enthusiasm makes us experience more life
D. enthusiasm helps us to succeed to a greater degree
2. From the example of the Nobel Prize winner Barbara Mc Clitock, we may find ____.
A. enthusiasm can encourage us in difficult times
B. enthusiastic people always get a deep pleasure from work
C. you can't make any achievement if you have no enthusiasm
D. enthusiastic people are sure to gain great fame in the end
3. The underlined sentence in Paragraph 3 suggests _____.
A. time and tide wait for no man              
B. we grow old as time goes on
C. people feel young with enthusiasm          
D. our soul becomes old with enthusiasm
4. The main idea of the last paragraph is ____.
A. enthusiasm can give us pleasure, though we have to sweat
B. we should try heart and soul to win what we want
C. we have not enough money to buy what we need
D. enthusiasm with sweat is what we need

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科目：高中英語 來源：河北省期中題 題型：閱讀理解

閱讀理解。
     Do you enjoy reading? Here readers of your age from all over the United States recommend (推薦) great
books for you to read:
     My favorite book is Don't Die, My Love by Lurlene McDaniel. I love all her books, but this was the first
one I read and I have to say, it is by far my favorite. It doesn't end like other books, and I cried while reading.
     I think Nancy Drew is great! Nancy is a detective (偵探) who has many fantastic ideas! I love it because
it's a book from when my grandma was my age, and I can share the fun with her!
     I highly recommend Skinny Bones by Barbara Park. It is funny so please add it on your book list. You
don't want to miss out funny stories!
     I would suggest ______ by Judy Blume. It is based on real things that happened to Judy Blume. It is about
a girl, Alice, who meets some girls at a new state. They become friends, make a club and meet once a week.
They stop after two weeks because they all like a boy in their class and put him as number one. I think every
girl should read this because it is about our growing up.
      I read a book called Neela: Victory Song and it was so good I read it twice! It takes place in India in 1936
and this 12-year-old girl named Neela tries to save her father! It has lots of history in it! I also learned a lot
about different cultures! The author's name is Chitra Banerjee Divakaruni.
1. According to the reader, Skinny Bones can be described as a ________ story.
A. sad
B. history
C. funny
D. detective
2. From which book can we learn different cultures?
A. Skinny Bones.
B. Nancy Drew.
C. Don't Die, My Love.
D. Neela: Victory Song.
3. The best name of the 4th book is ________.
A. My Secret
B. Growing Trouble
C. Three Friends
D. Alice Learns a Lesson
4. Which is TRUE about Nancy Drew?
A. Both the reader and the reader's grandma love this book.
B. It's based on real things that happened to the author.
C. It's about a12-year-old girl who tries to save her father.
D. It doesn't have a common ending like other books.

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科目：高中英語 來源：浙江省期末題 題型：閱讀理解

閱讀理解
     Ever since Jerusha started her college, she began to write letters. Through a series of letters, from freshman to senior in college, she shared her life and study with an unknown gentleman, who never wrote back. Here is the very first letter.
Dear Mr. Kind,    
     Here I am! I traveled yesterday for four hours in a train. It's a funny experience. I never rode in one
before.    
     College is the biggest, most confusing place - I get lost whenever I leave my room. I will tell you more
later when I'm feeling less puzzled. Now I want to write a letter first just to get me familiar to you.    
     It seems strange to be writing letters to somebody you don't know. It seems strange for me to be
writing letters at all - I've never written more than three or four in my life, so please overlook it if they are
not a model kind.    
     Before leaving yesterday morning, Mrs. Lippett and I had a very serious talk. She told me how to
behave, especially towards the kind gentleman who is doing so much for me. I must take care to be very
respectful.    
      I have been thinking of you a great deal this summer; having somebody take an interest in me after all
these years makes me feel as though I had found a sort of family. It seems as though I belonged to
somebody now, and it's a very comfortable feeling. I must say, however, that when I think about you, my
imaqination has very little to work upon.     
     There are just three things that I know:    
     I .You are tall.    
     II .You are rich.     
     III. You hate girl.    
     I suppose I might call you Dear Mr. Girl-Hater. Only that's rather unpleasant to me. Or Dear Mr. Rich-Man, but that's unpleasant to you, as though money were the only important thing about you. Maybe you won't stay rich all your life; But at least you will stay tall all your life! So I decide to call you Dear
Daddy-long-legs. I hope you won't mind. It's just a private pet name - we won't tell Mrs. Lippett. The
ten o'clock bell is going to ring in two minutes. Our day is divided by bells. We eat and sleep and study by bells. There it goes! Lights out. Good night.     
     You can see how strictly I obey rules due to my training in the John Grier Home.
                                                                                                                   Yours most respectfully,
                                                                                                                          Jerusha Abbott
1. Which of the following is NOT the reason for Jerusha to write the letter to Mr.Kind?                          
A. To get her familiar to him.                                                                                  
B. To present her thankfulness to him.                                                                          
C. To share her brand-new college life with him.                                                                
D. To apologize to him for not writing letters too often.                                                        
2. If Mrs. Lippett learned that the writer calls the man she writes to Daddy-long-legs, she would
probably_____.      
A. burst into laughter                                                                                          
B. think it acceptable                                                                                          
C. criticize the writer                                                                                          
D. inform the man                                                                                                
3. By "when I think about you, my imagination has very little to work upon.", the writer intends to tell us
that_____.
A. the man she writes to is dull and boring                                                                      
B. she is not familiar with the one she writes to                                                                
C. it is not interesting at all to write to a stranger                                                          
D. she lacks imagination when it comes to writing a letter                                                      
4. Jerusha was probably _____while she worked on the letter.                                                
A. curious                                                                                                      
B. light-hearted                                                                                                
C. serious            
D. skeptical

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科目：高中英語 來源：同步題 題型：閱讀理解

     Exploit your parking space
     An unused parking space or garage can make money. If you live near a city center or an airport, you
could make anything up to￡200 or￡300 a week. Put an advertisement (廣告) for free on Letpark or
Atmyhousepark.
     Rent (出租)a room
     Spare room? Not only will a lodger (房客)earn you an income, but also, thanks to the
governmentbacked "rent a room" program, you won't have to pay any tax on the first ￡4,500 you make
per year. Try advertising your room on Roomspare or Roommateeasy.
     Make money during special events
     Don't want a fulltime lodger? Then rent on a shortterm basis. If you live in the capital, renting a room
out during the Olympics or other big events could bring in money. Grashpadder can advertise your space.
     Live on set
     Renting your home out as a "film set" could earn you hundreds of pounds a day, depending on the film
production company and how long your home is needed. A quick search on the Internet will bring up
dozens of online companies that allow you to register your home for free-but you will be charged if your
home gets picked.
     Use your roof
     You need the right kind of roof, but some energy companies pay the cost of fixing solar equipment
(around ￡14,000)and let you use the energy produced for nothing. In return, they get paid for unused
energy fed back into the National Grid. However, you have to sign a 25year agreement with the supplier, which could prevent you from changing the roof.
1. If you earn ￡5,000 from renting a room in one year, the tax you need to pay will be based on
________.
A. ￡300  
B. ￡500
C. ￡4,500  
D. ￡5,000
2. Where can you put an advertisement to rent out a room during a big event?
A. On Letpark.  
B. On Roomspare.
C. On Grashpadder.  
D. On Roommateeasy.
3. If you want to use energy free, you have to ________.
A. sign an agreement with the government
B. pay around ￡14,000 for the equipment
C. sell the roof to some energy companies
D. keep the roof unchanged within 25 years
4. For whom is the text most probably written?
A. Lodgers.  
B. Advertisers.
C. House owners.  
D. Online companies.

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科目：高中英語 來源：0127 模擬題 題型：閱讀理解

閱讀理解。
A. Causes of overusing fluoride ( 氟化物 )
B. Negative effects of fluoride
C. Safe use of fluoride
D. The expert's background information
E. No need to worry about fluoride poisoning
F. Solutions to improper use of fluoride
     I have heard that fluoride can help stop dental decay, but I recently read that it is poisonous. Which of
these is true? How can children use fluoride safely?
1. (     )
     This question is answered by Dr Marcia M. Rich who practises general dentistry in Newholt. She is also
a lecturer at the University and a writer for the monthly magazine Your Dentist Cares.
2. (     )
     My answer to the first question is to stress that fluoride works well and is safe when users follow
instructions. Young children have a tendency to swallow toothpaste, which is why they should only have a
tiny amount of fluoride toothpaste on their toothbrush. If this simple measure is taken, parents can be
confident that children will be protected against tooth decay, and come to no harm.
3. (     ) 
      Almost all medicines have a negative effect-or even be deadly-if they are not taken as directed. So you
are right-fluoride can be poisonous if it is swallowed in very large quantities. It is for the reason that fluoride
supplements can only be obtained on prescription from the doctor or dentist. Please be assured that fluoride
overdoses are rare-in fact, I have never heard of any fatal incidents related to fluoride poisoning.
4. (     )
     Scientific studies have shown that fluoride can help to prevent cavities(牙洞) as long as it is used
correctly. If fluoride is abused, there is a risk of illness or even deaths in extreme cases. If a deadly amount
of fluoride is taken, immediate first-aid could save a life. A person who has swallowed a large amount of
fluoride will probably start vomiting. If not, the patient should be given milk or antacid and taken to the
nearest hospital for emergency treatment.
5. (     )
     Taking too much fluoride while teeth are growing can lead to a condition called dental fluorosis. The most
likely cause is the swallowing of fluoride toothpastes by young children. It can also be caused by inappropriate
use of fluoride drop or other fluoride supplements, for example when fluoride is already present in drinking
water.

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科目：高中英語 來源：同步題 題型：閱讀理解

閱讀理解
      Skeptics are a strange lot.Some of them refuse to admit the serious threat of human activities to the
environment, and they are tired of people who disagree with them.Those people, say skeptics, spread
nothing but bad news about the environment.The "ecoguilt" brought on by the discouraging news about our planet gives rise to the popularity of skeptics as people search for more comforting worldviews.
       Perhaps that explains why a new book by Bjorn Lomborg received so much publicity.That book, The Skeptical Environmentalist, declares that it measures the "real state of the world" as fine.Of course, another explanation is the deep pockets of some big businesses with special interests.Indeed, Mr Lomborg's
views are similar to those of some industryfunded organizations, which start huge activities through the
media to confuse the public about issues like global warming.
      So it was strange to see MrLomborg's book go largely unchallenged in the media though his beliefs
were contrary to most scientific opinions.One national newspaper in Canada ran a number of articles and
reviews full of words of praise, even with the conclusion that "After Lomborg, the environmental movement will begin to die down."
      Such onesided views should have immediately been challenged.But only a different review appeared in Nature, a respected science magazine with specific readership.The review remarked that Mr Lomborg's "preference for unexamined materials is incredible (不可信的)".
     A critical (批判的) eye is valuable, and the media should present information in such a way that could
allow people to make informed decisions.Unfortunately, that is often inaccessible as blocked by the
desire to be shocking or to defend some special interests.People might become halfblind before a world
partially exhibited by the media.That's a shame, because matters concerning the health of the planet are far too important to be treated lightly.

1. According to the passage, which of the following may be regarded as "skeptics" ?

A. People who agree on the popularity of "ecoguilt". 
B. People who disbelieve the serious situation of our planet.
C. People who dislike the harmful effect of human activities.
D. People who spread comforting news to protect our environment.

2. Which of the following can be a reason for the popularity of Lomborg's book?

A. Some big businesses intend to protect their own interests.
B. The book challenges views about the fine state of the world.
C. The author convinces people to seek comforting worldviews.
D. Industryfunded media present confusing information.

3. The author mentioned the review in Nature in order to ________.

A. voice a different opinion
B. find fault with Lomborg's book
C. challenge the authority of the media
D. point out the value of scientific views

4. What is the author's main purpose in writing the passage?

A. To encourage the skeptics to have a critical eye.
B. To warn the public of the danger of halfblindness with reviews.
C. To blame the media's lack of responsibility in presenting information.
D. To show the importance of presenting overall information by the media.

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