题目内容

We all enjoy the beautiful show of colors as leaves change each autumn. But did you ever wonder how and why this happens? To answer the question, first you have to understand what leaves are and what they do.

Leaves are nature’s food factories. Plants take water from the ground through their roots. And they take a gas called carbon dioxide from the air. Plants use sunlight to turn water and carbon dioxide into glucose (葡萄糖). Glucose is a kind of sugar. Plants use glucose as food for energy and as a building block for growing.

The way plants turn water and carbon dioxide into sugar is called photosynthesis (光合作用). That means, “putting together with light”.

A chemical called chlorophyll (叶绿素) helps photosynthesis. Chlorophyll is what gives plants their green color. As summer ends and autumn comes, the days get shorter and shorter. This is how trees “know” to begin getting ready for winter.

During winter, there is not enough light or water for photosynthesis. Trees rest during this time and live off the food they stored during the summer. They begin to shut down their food-making factories.

The green chlorophyll disappears from the leaves. As the bright green fades away, we begin to see yellow and orange leaves. Small amounts of these colors have been in the leaves all along. We just can’t see them in the summer, because they are covered up by the green chlorophyll.

The bright reds and yellows we see in leaves are made mostly in autumn. In some trees, like maples, glucose is caught in the leaves after photosynthesis stops. Sunlight and the cool nights of autumn turn this glucose into a red color. The brown color of trees like oaks (橡树) is made from waste left in the leaves.

It is the mixture of all these things that makes the beautiful colors we enjoy during autumn.

 

36. Which of the following about chlorophyll is NOT true?

A. Without it photosynthesis couldn’t happen.

B. It is the reason why leaves have their green color.

C. It turns the leaves red during autumn.

D. It is a chemical that’s important for trees’ food making.

37. From the text we can see that photosynthesis _____.

A. can produce glucose, which can provide energy for trees’ growth

B. can happen whenever there is light and water

C. is the process of putting sunlight together with chlorophyll

D. doesn’t stop during the trees’ lifetime even in winter

38. What’s the author’s purpose of writing the passage?

A. To explain the process of trees’ photosynthesis.

B. To encourage readers to protect the environment.

C. To analyze the reasons why leaves change colors.

D. To help readers understand what leaves and trees are.

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     I first went to hear a live rock concert when I was
eight years old. My brother and his friends were all   1   of a
heavy metal group called Black Wednesday. When they   2   that
Black Wednesday were going to perform at our local theatre, they all
bought   3   for performance. However, at the last minute, one of
the friends couldn't go, so my brother  4   me the ticket.I was
really   5   !
      I remember the buzz (嘈杂声)of excitement inside the theatre
as we all found our  6  . After a few minutes, the lights went
down and everybody became   7   .I could barely make out the
stage in the  8  . We waited. Then there was a roar from the
crowd, like an explosion, as the first members of the band  9 
the stage. My brother leaned over and shouted something in my ear,
but I couldn't 10 what he was saying. The first song was already
starting and the music was as  11  as a jet engine.I could  12 
the drum beats and bass notes in my stomach.
     I can't recall any of the songs that the band played. I just
  13  that I really enjoyed the show and didn't want it to   14    .
But in the end, after three encores (加演), the show finished. We
left the  15  and walked unsteadily out onto the pavement.I felt a
little dizzy, as if I had just   16  from a long sleep. My ears were
still    17    with the beat of the last song.
      After the 18 , I became a Black Wednesday fan too for a
few years before getting into other kinds of music. Once in a while,
 19 , I listen to one of their songs and  20   I'm back at that
first show.
(     )1. A. members    
(     )2. A. guessed    
(     )3. A. flowers    
(     )4. A. booked      
(     )5. A. relaxed    
(     )6. A. seats      
(     )7. A. comfortable
(     )8. A. silence    
(     )9. A. fell upon  
(     )10. A. forget    
(     )11. A. loud      
(     )12. A. feel      
(     )13. A. realize    
(     )14. A. continue  
(     )15. A. party      
(     )16. A. escaped    
(     )17. A. aching    
(     )18. A. competition
(     )19. A. though    
(     )20. A. decide    
B. friends    
B. discovered
B. drinks    
B. offered    
B. embarrassed
B. entrance  
B. quiet      
B. noise      
B. got through
B. hear      
B. heard      
B. touch      
B. understand
B. delay      
B. theatre    
B. traveled  
B. burning    
B. performance
B. otherwise  
B. regret    
C. fans      
C. thought    
C. clothes    
C. returned  
C. excited    
C. spots      
C. senous    
C. darkness  
C.  broke into
C. repeat    
C. sweet      
C. enj oy    
C. believe    
C. finish    
C. opera      
C. benefited  
C. ringing    
C.  interview
C. instead    
C. conclude  
D. volunteers    
D. predicted    
D. tickets      
D. found        
D. encouraged    
D. space        
D. nervous      
D. smoke        
D. stepped onto  
D. bear          
D. fast          
D. digest        
D. remember      
D. change        
D. stage        
D. woken        
D. rolling      
D. celebration  
D. besides      
D. imagine      

As most university students are packing their bags,boarding trains or flying home for the Spring Festival,some will stay behind to spend the holiday on campus.

Zhou Yunyun,22,a senior finance major at Jilin University,has decided that instead of traveling to Hainan province,he will kill the time by playing computer games with his online friends.

“I'm used to chatting and playing with them every day.It’s just fun to make friends this way,”he said.“When I returned home in past years,my relatives always asked me a lot of questions about my plans after graduation.They had high expectations of me,which made me feel stressed,” said Zhou.

The campus,usually lively,will probably turn into a death town,with most restaurants,shops and student centers closed during the break.But there are also a few advantages,according to Jia Debao,2 1,a junior majoring in administration at China Agricultural University.“I might feel a bit lonely,but at least I can stay away from my parents’ complaining and enjoy the peaceful and quiet stay,” he said.“More importantly,I can enj oy the high speed of the Internet,I can always find empty seats in classrooms,and I don’t have to wait to use the bathroorm” But education experts recommend students who stay on campus to come up with more interactive plans.That’s because communication on the Internet can’t replace real life interpersonal relationships.

Society has promoted a kind of“couch potato" or close-in culture among some young people, according to Shi Tongyu, a researcher at the Chinese Academy of Social Sciences. He warned that this kind of lifestryl can damage students’ mental and physical development.

 “When you constantly stare at a computer screen and type on your keyboard,you gradually lose the ability to socialize and survive normally,"said Shi.“A human’s most important task is to survive,which cannot be completed by staying at home all the time. Instead,it must be achieved through real life experience and communication.”

39.What can we learn about Zhou Yunyun?

       A.He feels very lonely on campus.

       B.He will promote close-in culture.

       C.He will spend the Spring Festival with relatives.

       D.He will spend the Spring Festival with on-line friends.

40.Spending the Spring Festival on campus for Jia Debao means          .

       A.he will miss his parents a little bit

       B.there will be more seats in classrooms

       C.he will have a quiet and peaceful break

       D.the speed of the Internet will get faster

41.The underlined phrase“couch potato” is closest in meaning to         .

       A.inactive person                                                                        B.close friend

       C.sociable student                                   D.addicted gamer

42.What do education experts recommend students to do?

       A.To do some traveling.

       B.To stay more with families.

       C.To find empty seats in classrooms.

       D.To experience real lire and communication.

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