题目内容

An early invention by Albert Einstein has been rebuilt by scientists at Oxford University. They are trying to develop an environmentally friendly refrigerator that runs without electricity.

We all know that modern fridges cause damage to the environment. They work by using a kind of man-made greenhouse gas called Freon (氟里昂), which is far more damaging than carbon dioxide.

Now Malcolm McCulloch, an electrical engineer at Oxford, is leading a three-year project to develop appliances that can be used in places without electricity.

His team has completed a prototype (样机) of a fridge patented in 1930 by Einstein. It used only pressurized gases to keep things cold. The design was partly used in the first refrigerators, but the technology was dropped when more efficient compressors (压缩机) became popular in the 1950s. That meant a switch to using Freon.

Einstein’s idea uses butane (丁烷) and water and takes advantage of the fact that liquids boil at lower temperatures, when the air pressure around them is lower.

“If you go to the top of Mount Qomolangma, water boils at a much lower temperature than it does when you’re at sea level and that’s because the pressure is much lower up there,” said McCulloch.At one side is the evaporator (蒸发器), a bottle that contains liquid butane. “If you introduce a new vapor above the butane, the liquid boiling temperature decreases and, as it boils off, it takes energy from the surroundings to do so,” says McCulloch. “That’s what makes it cold.”

The gas fridges based on Einstein’s design were replaced by Freon-compressor fridges partly because Einstein’s design was not very efficient. But McCulloch thinks that by changing the design and replacing the types of gases used it will be possible to quadruple (翻两番) the efficiency.

However, McCulloch’s fridge is still in its early stages. “It’s very much a prototype,” he said. “Give us another month and we'll have it working.”

72.According to the passage, an early invention by Albert Einstein _______.

A.has been rediscovered because it costs much less and works more efficiently

B.is being redesigned because it could be used in places without electricity

C.has just been found to be energy-saving and environmentally friendly

D.will be fully made use of and become the fridge of the future

73.Which of the following is TRUE according to the text?

A.Freon was used in fridges long before the 1950s.

B.Freon is what makes current fridges big polluters.

C.McCulloch thinks he could improve Einstein's design by using other types of vapors.

D.The fridge Malcolm McCulloch and his team designed will be put into production soon.

74.We can learn from the text that the prototype completed _______.

A.changed the air pressure around it

B.was tested on the top of Mount Everest

C.increased the liquid boiling temperature

D.used only pressurized gases to keep things cold

75.McCulloch’s words in Paragraph 6 _____.

A.serve as an explanation for the principle behind Einstein’s fridge

B.give you the reason why Einstein’s fridge was not efficient

C.tell you how to take advantage of low air pressure

D.show you how Einstein’s fridge works

72-75 BBDA


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阅读下面短文,从短文后所给各题的四个选项(A、B、C和D)中,选出可以填入空白处的最佳选项。

  It was an early September day,cool and bright and just right for running,and I was in the first few miles of a 10 mile race over a course with a few high hills,  1  ,I felt energetic;despite the hills,it going to be a   2   run.

  Just ahead of me was Peggy,a teacher from Mount Kisco.She was too running   3  ,moving along at my speed.The pace felt comfortable,so I decided to   4   where I was.Why pay attention to pace when she was setting such a good one?I'd overtake her   5   when she was tired.

  So I ran behind her,The course   6   north for five miles,wandered west for a hilly mile,then turned south again along a winding road.The race was getting   7  .We had four miles   8   and already it was beginning to be real work.

  Peggy overtook a young runner.She seemed to   9   him,for they exchanged a few cheerful words as she passed him.Their exchange   10   me.

You don't chat during a race   11   you are feeling good and Peggy plainly was.

  Sill,I was   12   enough to overtake her if she was tired,so I didn't give up hope completely.We were getting nearer to a tong,punishing hill now and it would be the   13  .We were a mile from tile finish line,  14   whatever happened on the hill would almost certainly determine who crossed it first.

  As I moved up the hill,my   15   wandered for a few minutes.When I   16  ,Peggy was moving away— first five yards,then ten,then more.Finally it was clear that there was no   17   of catching her.She beat me soundly.

  There is an important   18   in that race,Women are thought to be weaker,slower and not nearly   19   skilled in sport.Yet as Peggy so clearly showed,the similarities between men and women runners are more important than the differences.I have run with   20   women,and I can say that it is often hard work.

(1)

[  ]

A.

Still

B.

Even

C.

What's more

D.

However

(2)

[  ]

A.

tiring

B.

ashamed

C.

fine

D.

competitive

(3)

[  ]

A.

fast

B.

slowly

C.

happily

D.

easily

(4)

[  ]

A.

stick to

B.

stay

C.

run

D.

keep

(5)

[  ]

A.

soon

B.

in the end

C.

later on

D.

sooner or later

(6)

[  ]

A.

went

B.

headed

C.

rounded

D.

lasted

(7)

[  ]

A.

harder

B.

faster

C.

more tiring

D.

easier

(8)

[  ]

A.

going

B.

in all

C.

after all

D.

left

(9)

[  ]

A.

like

B.

get on well with

C.

know

D.

love

(10)

[  ]

A.

worried

B.

disappointed

C.

displeased

D.

discouraged

(11)

[  ]

A.

if

B.

unless

C.

while

D.

as

(12)

[  ]

A.

energetic

B.

determined

C.

close

D.

young

(13)

[  ]

A.

test

B.

exam

C.

sheck

D.

highest

(14)

[  ]

A.

and

B.

because

C.

so

D.

but

(15)

[  ]

A.

thought

B.

attention

C.

mind

D.

heart

(16)

[  ]

A.

looked down

B.

looked up

C.

came back

D.

ran up

(17)

[  ]

A.

chance

B.

possibility

C.

time

D.

hope

(18)

[  ]

A.

class

B.

lesson

C.

teaching

D.

sense

(19)

[  ]

A.

as

B.

such

C.

very

D.

same

(20)

[  ]

A.

very few

B.

a number of

C.

a few

D.

too many


That holiday morning I didn’t have to attend school. Usually, on holidays, Mother   36  me to sleep in. And I would certainly take full advantage of it. On this particular morning,  ___37___,I felt like getting up early.
I stood by my window overlooking the ___38___, having nothing better to do. But as it turned out, I was soon to learn about something ___39___ in life.
As I watched several people go by, get into their cars and drive off, I ___40___ an old man on a bicycle with a bucket on its ___41___ and a basket rags and bottles on its back-carriage. He ___42___ from one car to another, washing and cleaning them. From the water on the ground, it seemed that he had already ___43___ washing and cleaning about a dozen or more cars. He must have begun to work quite early in the morning.
Several thoughts ___44___my mind as I watched him work. He wasn’t well-dressed. He had on a pair of shorts and a(n) ___45___ T-shirt. The bicycle he rode was not by any means the kind modern ___46___would want to be seen riding on. But he seemed___47___ with life. There he was, working hard at his small business, ___48___ at passers-by and stopping to chat now and then ___49___ elderly men and women on their way to the market nearby.
There was a noticeable touch of___50___ in the way he seemed to be doing things— ___51___the windscreen (挡风玻璃), then standing back to admire it; scrubbing (擦净) the wheels and ___52___, standing back to see what they look like after the scrub.
It was a ___53___ to learn, I felt. At no age need one have to beg for a ___54___if one has good health and is willing to work hard. For a while I felt ___55__ of myself. Young as I am—just sixteen, and there was this old man who must have been usefully engaged perhaps before the sun appeared above the horizon.

【小题1】
A.forcesB.allowsC.causesD.forbids
【小题2】
A.otherwiseB.thereforeC.howeverD.besides
【小题3】
A.parking lotB.bus stopC.schoolD.market
【小题4】
A.interestingB.surprisingC.awful D.useful
【小题5】
A.noticedB.recognizedC.calledD.assisted
【小题6】
A.backB.handleC.wheelD.seat
【小题7】
A.searchedB.leftC.movedD.wandered
【小题8】
A.stoppedB.startedC.intended D.finished
【小题9】
A.crossedB.slippedC.disturbedD.inspired
【小题10】
A.attractiveB.shinyC.simpleD.expensive
【小题11】
A.repairmenB.businessmenC.driversD.cyclists
【小题12】
A.busyB.contentC.carefulD.bored
【小题13】
A.wavingB.lookingC.laughingD.pointing
【小题14】
A.aboutB.forC.withD.like
【小题15】
A.worryB.respectC.sympathyD.pride
【小题16】
A.cleaningB.fixingC.replacingD.covering
【小题17】
A.stillB.yetC.againD.soon
【小题18】
A.lessonB.subjectC.skill D.fact
【小题19】
A.businessB.livingC.successD.right
【小题20】
A.tiredB.doubtfulC.fearfulD.ashamed

Are morning people born or made? In my case it was definitely made.In my early 20s, I rarely went to bed before midnight, and I would almost always get up late the next morning.
But after a while I couldn’t ignore the high relationship between success and rising early.On those rare occasions where I did get up early, I noticed that my productivity was almost always higher.So I set out to become a habitual early riser.But whenever my alarm went off, my first thought was always to stop that noise and go back to sleep.Eventually some sleep research showed me that I was using the wrong strategy.
The most common wrong strategy is this: You assume that if you’re going to get up earlier, you’d better go to bed earlier.It sounds very reasonable, but will usually fail.
There are two main schools(流派) of thought on sleep patterns.One is that you should go to bed and get up at the same time every day.The second school says you should go to bed when you’re tired and get up when you naturally wake up.However, I have found both of them are wrong if you care about productivity.If you sleep at set hours, you’ll sometimes go to bed when you aren’t sleepy enough.You’re wasting time lying in bed awake and not being asleep.
If your sleep is based on what your body tells you, you’ll probably be sleeping more than you need.Also, your mornings may be less predictable if you’re getting up at different times.
The solution for me has been to combine both methods.I go to bed when I’m sleepy and get up with an alarm clock at a fixed time.So I always get up at the same time (in my case 5 am), but I go to bed at different times every night — sometimes at 9:30pm, and other times at midnight.Most of the time I go to bed between 10-11 pm.
However, going to bed only when I’m sleepy, and getting up at a fixed time every morning is my way.If you want to become an early riser, you can try your own.
【小题1】According to the passage, the underlined phrase refers to ____.

A.people who stay up until the next morning.
B.people who get up early in the morning.
C.people who feel sleepy in the morning.
D.people whose productivity is the highest in the morning.
【小题2】Why did the author want to become a habitual early riser?
A.Because he / she wanted to form the habit of going to bed early and getting up early.
B.Because he / she had found that his / her productivity was higher when he / she got up early.
C.Because he / she wanted to see which of the two main schools of thought on sleep patterns was right.
D.Because he / she was told the high relationship between success and rising early.
【小题3】The author experienced all the following EXCEPT ____.
A.going to bed after midnight.
B.getting up early occasionally.
C.pressing off the alarm to go on sleeping.
D.asking scholars for advice on sleeping habits.
【小题4】The passage is mainly about ____。
A.how to become an early riser.
B.how to have good sleep.
C.wrong strategies for getting up early.
D.main schools of thought on sleep patterns.

 The other day I decided to come home early because it was such a beautiful day. The      were outside playing in my apartment complex (公寓大楼) and the ice cream truck was whistling its tune. As I       slowly to avoid an accident, I noticed a little boy       at the ice cream truck. He didn’t get anything and he walked away with a       look on his face. I asked the ice cream seller what happened and he said the little boy had no      . I had no cash on me so I drove to my building and went upstairs to       some cash. When I found it, the ice cream seller was       waiting but the little boy had      .

I went in the      I thought he might have gone and I saw a       getting out of her vehicle. I asked her if she had a little boy and she said yes. She then told me that she and her son had gone to the grocery store the day before and had       ice cream but she did not have enough money to buy        .

She quickly went into the        to get her son, and when she        several minutes later, I realized that he was not the         little boy I had seen. This boy was a bit older and his sister came out with him. I took them both to the truck and let them         out what they wanted.

I        told the mom it was not the same boy I was talking about. I        myself to the mother properly and         my baby-sitting services free of charge if she ever needed them. 1 couldn't find the original boy        but 1 hope he gets some ice cream soon.

1.A. cats                 B. kids                      C. dogs                     D. students

2.A. walked                          B. ran                      C. climbed           D. drove

3.A knocking                  B. shooting                   C. lying                   D. looking

4.A. puzzled                         B. curious          C. disappointed          D. delighted

5.A. excuse                          B. money                     C. parents          D. friends

6.A put away                        B. look for                   C. borrow          D.  lend

7.A. still                           B. anxiously                  C. doubtfully               D. nervously

8.A. left                           B. appeared                 C. cried                        D. escaped

9.A. station                     B. line                            C. sight                   D. direction

10.A. woman                  B. girl              C. granny                      D. conductor

11.A. chosen                  B. ordered          C. wanted     D. eaten

12.A. it                             B. ones                          C. them                  D. those

13.A. house                    B. shop                    C. truck                         D. market

14.A. disappeared              B. returned                 C. waited                     D. stayed

15.A. lost                     B. strange          C. short                        D. same

16.A. look                   B. pick                    C. speak                        D. make

17.A. never                          B. seldom           C. often                  D. ever

18.A. explained                   B. admitted                 C. devoted                  D. introduced

19.A. denied                  B. resigned                   C. offered          D. operated

20.A. somewhere               B. everywhere           C. anywhere          D. nowhere

 

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