In fall 2006.the National Basketball Association (NBA)started using basketballs made with synthetic .or man-made .material instead of leather．They made the change be- cause they wanted every basketba 题目和参考答案——青夏教育精英家教网—

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In fall 2006，the National Basketball Association （NBA）started using basketballs made with synthetic ，or man-made ，material instead of leather（皮革）．They made the change be- cause they wanted every basketball they use to feel and bounce（弹起）the same．Not all leather balls are exactly alike in weight or how they bounce，but the synthetic balls are．

However，some players complained right away that the new balls bounced differently and were actually harder to control than the leather ones．

Physics helped answer questions about why the new balls felt different．For example，the scientists studied friction（摩擦力），which in this case affects the ability of a player to hold onto a ball．"The greater the friction，the better it will stick to his hand，"explains a scientist．

Tests on both wet and dry balls showed that while the synthetic ball was easier to hold onto when dry，it had less friction and became much harder to hold onto when wet．That's because sweat（汗水） stays on the surface of the synthetic balls but gets taken into the leather balls．

The scientists also tested bounce and found that the logo （商标）printed on the new balls made their surface uneven（不平） and caused them to bounce a little strangely com- pared with the leather balls．

In January，the NBA went back to using the leather bails．They aren't perfect，but for now，that's just the way the ball bounces．

1．Why were the synthetic balls expected to be used in NBA according to the text?

A．Because they are easier to control． B．Because they waste less material．

C．Because they look exactly alike． D．Because they feel and bounce alike．

2．The ball is easier to hold on to_________

A．when friction is greater B．when friction is less

C．when it is heavier D．when it bounces strangely

3．The synthetic ball bounces differently from the leather one mainly because _________

A．it is wet B．it is dry

C．there's a logo on it D．its weight remains the same

4．It can be inferred（推断） from the text that _________．

A．a synthetic ball takes in water faster than a leather ball

B．a leather ball is more difficult to make than a synthetic one

C．a synthetic ball is more expensive than a leather ball

D．a leather ball may increase its weight during a game

5．The underlined word" They" in the last paragraph refers to __________．

A．the synthetic balls B．the leather balls

C．the ball players D．the scientists

DACDB

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Now, an hour before classes start, every seat in the library is taken by students who cannot wait for getting online. Fifth-grade teacher Jen Friday talks about different kinds of birds as students view them at a colorful website. After school, students on buses pull laptops from backpacks to get started on homework. Since the computer arrived, enrollment is up 20%. Scores on state tests are up 35%.

Indeed, school systems in rural Maine and New York City also hope to follow Arace Middle School’s example. Governor Angus King had planned using $50 million to buy a laptop for all of Maine’s 17,000 seventh-graders – and for new seventh-graders each fall.

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Back in Bloomfield, in the meantime, most of the kinks have been worked out. Some students were using their computers to visit unauthorized（非法的）websites. But teachers have the ability to keep an eye on where students have been on the Web and to stop them. “That is the worst when they disable you,” says eighth-grade honors student Jamie Bassell. The habit is rubbing off on parents. “I taught my mom to use e-mail,” says another eighth-grader, Katherine Hypolite. “And now she’s taking computer classes. I’m so proud of her!”

1.The example of Carmen Arace Middle School in the passage is used to ______.

A. show the problems schools are faced with today

B. prove that a school without high enrollment can do well

C. express the importance of computers in modern education

D. tell that laptops can help improve students’ school performance

2.According to the writer, students in New York City’s public schools will ______.

A. enjoy e-mail service in the near future

B. make money by selling ads on websites

C. all have their own laptops within nine years

D. become more interested in their studies with laptops

3.The underlined word “kinks” in the last paragraph most probably means ______.

A. plans B. projects C. problems D. products

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A. a school Internet portal is the key to a laptop program

B. the laptop program also has a good influence on parents

C. students slowly accept the fact their online activities controlled

D. the laptop program in public school is mainly for the eighth-graders

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I asked many people, why? What was I doing ___18____? “Nothing,” most of them replied. “Just ____19____.” So I waited, waited and waited.

I ____20____ off the deck （露台）, I changed the feed, I ___21____ the feeders, and I ____22____ made the cat go out the other door! But ____23___ seemed to work. So --- I waited, “with patience and hope. ”

Two months later, early in the morning, I was ____24____. A beautiful bird had been on the bird feeder. All of a sudden, I saw hundreds upon hundreds of birds____25____ from everywhere.

____26____ a beautiful lesson this living thing taught me! “Patience and hope” will ____27____ the most beautiful things in life.

So I keep hoping and waiting, waiting and ___28____. I will try to use this “little lesson” in ____29____ many other things in my life. I guess, “____30____ is a virtue （美德）” after all.

1.A. little B. many C. much D. lot

2.A. so B. because C. however D. and

3.A. bad B. wrong C. well D. good

4.A. go B. sit C. watch D. wait

5.A. went B. put C. cleaned D. took

6.A. bought B. sold C. washed D. took

7.A. always B. hardly C. even D. sometimes

8.A. nothing B. everything C. something D. anything

9.A. sad B. surprised C. worried D. frightened

10.A. coming B. going C. leaving D. singing

11.A. That B. Which C. How D. What

12.A. spend B. take C. bring D. come

13.A. hoping B. dreaming C. watching D. asking

14.A. so B. such C. much D. very

15.A. dream B. patience C. volunteering D. lesson

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