题目内容

There’s a whole lot of things that people fill their stomachs with. Some of them keep people alive. Some of them taste good to people. Some of them help people win pie-eating contests. Alcohol does none of these things. Why do people keep drinking it? And what does it do once it gets to their stomachs?

There are all kinds of alcohol molecules (分子), but the one that people most often pour down their throat is ethanol (乙醇). Ethanol is very tiny and it dissolves in water, so it gets into all sorts of places that it’s not supposed to. Alcohol heads for the digestive system. Because it dissolves in water, it can get into the water in the bloodstream. Because ethanol, to a certain extent, can pass through cell membranes(膜). It can go almost anywhere. It spreads through the muscles, and is sweated — unmetabolized(未经新陈代谢的) and whole — through the skin. It gets into the heart. It even takes a walk through the brain, and this is the secret of its powers.

Alcohol depresses the nerves, and the nerves affect almost every area of the body. Enough alcohol makes people sleep, so people who become unconscious choke on their own vomit (呕吐物). Most worryingly, enough alcohol can shut down those parts of the brain just like any other parts. People become unconscious and their brains simply forget to breathe.

Alcohol is broken down in the liver. Alcohol doesn’t destroy the liver, but products that the liver breaks the alcohol into do cause damage. A glass of wine per day can not do any harm. Instead, it can prevent heart attacks or can make someone functionally young. And it is kind of nice to know that sometimes, relaxation and cheer can be bottled. All that’s needed is to take care how much alcohol is let into a person’s brain.

1.How does the author introduce the topic of the text?

A. By statement.B. By question.

C. By arguing.D. By explaining.

2.Why can alcohol reach the brain?

A. Because it can move through water molecules in the blood.

B. Because it is small enough to get through any narrow space.

C. Because it is so light that the bloodstream can transport.

D. Because it is absorbed only by the cells in the stomach.

3.What’s the main idea of Paragraph 3?

A. Alcohol affects the work of the nerves.

B. Alcohol has an effect on people’s breath .

C. People are drunk when their brains get drunk.

D. Drinking too much is quite dangerous.

4.From the passage, we can know ________.

A. many people like a drink when they feel relaxed

B. enough alcohol can control the brain activities

C. alcohol damages the liver indirectly

D. proper alcohol may lead to better sleep

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Here is an astonishing and significant fact: Mental work alone can't make us tired. It sounds absurd. But a few years ago, scientists tried to find out how long the human brain could labor without reaching a stage of fatigue(疲劳). To the amazement of these scientists, they discovered that blood passing through the brain, when it is active, shows no fatigue at all! If we took a drop of blood from a day laborer, we could find it full of fatigue toxins(霉素) and fatigue products. But if we took blood from the brain of an Albert Einstein, it would show no fatigue toxins at the end of the day.

So far as the brain is concerned, it can work as well and swiftly at the end of eight or even twelve hours of efforts as at the beginning. The brain is totally tireless. So what makes us tired?

Some scientists declare that most of our fatigue comes from our mental and emotional(情感的) attitudes. One of England's most outstanding scientists, J. A. Hadfield, says, “The greater part of the fatigue from which we suffer is of mental origin. In fact, fatigue of purely physical origin is rare.” Dr. Brill, a famous American scientist, goes even further. He declares, “One hundred percent of the fatigue of a sitting worker in good health is due to emotional problems.”

What kinds of emotions make sitting workers tired? Joy? Satisfaction? No! A feeling of being bored, anger, anxiety, tenseness, worry, a feeling of not being appreciated—those are the emotions that tire sitting workers. Hard work by itself seldom causes fatigue. We get tired because our emotions produce nervousness in the body.

1.What surprised the scientists a few years ago?

A.Fatigue toxins could hardly be found in a laborer's blood.

B.Albert Einstein didn't feel worn out after a day's work.

C.The brain could work for many hours without fatigue.

D.A mental worker's blood was filled with fatigue toxins.

2.According to the author, which of the following can make sitting workers tired?

A.Challenging mental work. B.Unpleasant emotions.

C.Endless tasks. D.Physical labor.

3.What's the author's attitude towards the scientists' ideas?

A.He agrees with them.

B.He doubts them.

C.He argues against them.

D.He hesitates to accept them.

4.We can infer from the passage that in order to stay energetic, sitting workers need to ________.

A.have some good food

B.enjoy their work

C.exercise regularly

D.discover fatigue toxins

完形填空

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

During the war, my husband was stationed at an army camp in a desert in California. I went to live there in order to be _________ him. I hated the place. I had never _________ been so unhappy. My husband was ordered out on a long-term duty, and I was left in a tiny shack(棚屋) alone. The heat was _________ —almost 125 °F even in the shade of a cactus(仙人掌). _________ a soul to talk to. The wind blew non-stop, and all the food I ate, and the very air I breathed, were _________ with sand, sand, sand!

I was so sorry for myself that I wrote to my parents. I told them I was _________ and coming back home. I said I couldn’t stand it one minute longer. I _________ be in prison! My father answered my_________ with just two lines—two lines that will always sing in my _________ — two lines that completely changed my life:

Two men looked out from prison bars,

One saw the mud, the other saw the stars.

I read those two lines _________ . I was ashamed of myself. I made up my mind I would find out what was good in my present _________ I would look for the stars.

I made friends with the natives, and their _________ amazed me. They gave me presents of their favorite artworks which they had _________ to sell to tourists. I studied the delightful forms of the cactus. I watched for the desert sunsets, and _________ for seashells that had been left there millions of years ago when the desert had been an ocean _________ .

What brought about this _________ change in me? The desert hadn’t changed, _________ I had. I had changed my _________ . And by doing so, I changed an unhappy experience into the most amazing _________ of my life. I was excited by this new world that I had discovered. I had looked out of my self-created prison and _________ the stars.

1.A. offB. behindC. nearD. beyond

2.A. beforeB. alreadyC. thenD. still

3.A. inflexibleB. incomprehensible

C. uncontrollableD. unbearable

4.A. OnlyB. NotC. ManyD. Such

5.A. coveredB. filledC. buriedD. charged

6.A. catching upB. keeping up

C. giving upD. getting up

7.A. ought toB. might wellC. would ratherD. had better

8.A. requestB. callC. questionD. letter

9.A. comparisonB. imaginationC. considerationD. memory

10.A. over and overB. by and by

C. up and downD. now and then

11.A. companyB. occupationC. situationD. relationship

12.A. movementB. reactionC. guidanceD. purpose

13.A. refusedB. failedC. managedD. happened

14.A. askedB. huntedC. waitedD. headed

15.A. floorB. surfaceC. rockD. level

16.A. shockingB. challengingC. puzzlingD. astonishing

17.A. asB. butC. forD. or

18.A. attitudeB. principleC. identityD. standard

19.A. vacationB. operationC. affairD. adventure

20.A. soughtB. countedC. foundD. reached

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