阅读理解阅读理解. Today, ultrasonicwaves are being put to work in laboratories and factories．If an ultrasound generator is placed in a liquid, the waves move the liquid back and forthhundreds of thousands 题目和参考答案——青夏教育精英家教网—

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阅读理解

阅读理解。

　　Today, ultrasonic(超声的)waves are being put to work in laboratories and factories．If an ultrasound generator is placed in a liquid, the waves move the liquid back and forthhundreds of thousands of times each second．This causes materials to mix quickly or to dissolve(使分解，使溶解)in liquids．Paint manufacturers(制造商)use ultrasound to do a better job of blending colors．The companies that make film for your camera find that mixing chemicals by the use of sound waves will produce a more sensitive film．

　　The new lightweight(轻量的)type of washing machine uses ultrasonic waves to get clothes clean．Its special ultrasound generator is put into a pail of soapy water containing the soiled clothes．The sound waves drive the soapy water back and forth through the cloth so fast that everything is soon clean．There is also a new kind of dishwasher that works in much the same way．

　　Ultrasonic waves can shake a liquid so fast that tiny holes form all through it．The liquid is actually torn apart by this action．Almost as soon as these holes are made, they fall together again．The result is a powerful pounding action．In the dairy industry this is used for the double purpose of making homogenized(使均匀，使匀质)milk and sterilizing(使无菌)it at the same time．If you look at some raw milk with a microscope, you find that it is made up of little drops of butter fat floating around in a watery liquid．In order to make milk easier to digest, these fat droplets(微粒)may be broken up by forcing the milk through very small openings．The result is called homogenized milk．When the ultrasonic method is used, the sound waves not only break up the droplets but also kill the germs in the milk by pounding them to pieces．

(1)

Why does a paint manufacturer use ultrasound to do a better job of blending colors?
[　　]
A．	Because it is cheap to use ultrasound to blend colors．
B．	Because the waves move the liquid so quickly that it can make materials mix quickly or dissolve in liquids．
C．	Because they can mix chemicals by the use of sound waves．
D．	Because the waves can clean the paint．

(2)

What properties does ultrasound wave have?
[　　]
A．	Homogenizes and sterilizes the milk．
B．	Mix materials and break droplets．
C．	Kill germs and sterilize milk．
D．	Move liquids quickly．

(3)

What exists in the raw milk?
[　　]
A．	Little drops of butter fat．
B．	Small holes．
C．	Fat droplets and germs．
D．	Chemicals．

(4)

Where is ultrasound wave not used?
[　　]
A．	In the paint manufacture．
B．	In the shop mixing bread flour．
C．	In the film-making company．
D．	In the dairy industry．

答案：1．B;2．D;3．C;4．B;

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相关题目

阅读理解

阅读下面短文，从每题所给的四个选项（A，B，C和D）中选出最佳选项。

If you have made an agreement to go out to eat with someone, you should be clear who is paying. If the other suggests you have lunch with him or her, you might simply say something like this:“I'm afraid it'll have to be some place inexpensive as I have very little money.”The other person may say,“OK, I'll meet you at McDonald's.”This means it is agreed that each person pays for his own meal, i. e. that you “go Dutch”. If the person says,“Oh, no. I'll take you to lunch in a little restaurant I like very much,”it means that the person wants to pay the bill for both of you. If you feel friendly towards this person, there's no reason why you should not accept this invitation by simply saying “Thank you. That would be very nice.”If a person invites you to his or her home for a meal, it's understood that person is paying. If you invite someone to your home, it's understood that you are buying the food. If you want to invite someone out for lunch, you must also make yourself clear by saying, perhaps,“I'd like to take you to lunch tomorrow at the Hostess Inn Coffee Shop”(meaning you plan to buy the food) or“let's have lunch together tomorrow at Burger King. It's on me.”American women used to expect men to pay for all meals, but today most women will pay for themselves. However, you should always make your position clear. Being clear is the polite thing to do. It is lack of clarity (明了) that causes loss of face in this situation.

1．According to the passage, if someone asks you to go out to eat, ________.

[　　]

A．it shows he wants to pay for you

B．it doesn't necessarily meant that he wants to pay for you

C．you should ask him to go out to eat next time

D．you should refuse him if you don't like him

2．The underlined part“go Dutch”means ________.

[　　]

A．each paying for himself

B．buying the food at a store

C．paying for the two of you

D．going to some inexpensive place

3．Which of the following is true according to the passage?

[　　]

A．Men are expected to pay for women when they are eating out.

B．One should accept another person's invitation if he isn't one's good friend.

C．“It's on me.”means“I'll pay for the meal.”

D．If you are invited to someone's house for a meal, you should bring some gifts.

3．In order not to lose face, ________.

[　　]

A．one should try to pay for others

B．one should not eat out without carrying a lot of money

C．one shouldn't let a woman pay for him

D．one should make oneself clear and understood

阅读理解

阅读下列文，从每题所给的A、B、C、D四个选项中，选出最佳答案。

One day newly-wedded (结婚的) Nancy lost her ring when they were busy working in their fields to plant potatoes. Friends were called and the field was searched long but in vain(无效的). Later, when the potatoes were harvested everyone looked out for the ring but it remained lost. Another year came round and all the farmers working in the fields kept their eyes open.

The following year was the same. And year after year, whoever had business in the fields always had Nancy's ring in his mind.

Then the farm changed hands but it went to further than to cousins (表兄弟). So the memory of the lost ring remained alive until thirty-eight years had passed. Then came a spring day when a man was plowing (耕地) the field behind a pair of horses. Even after thirty-eight years he still looked out for the ring, and knew just which part of the field Nancy had lost it in. At this time, when he came there, he found it. He picked it up, put it carefully into his pocket, left his horses, and ran all the way down to the village and placed it into Nancy's hand.

1．How did Nancy come to lose her ring? She lost it while ________.

A. helping to plant tomatoes in the fields

B. watering the plants in the fields

C. doing some plowing in the fields

D. gathering potatoes in the fields

2．What was done to try and find the lost ring?

A. Friends were asked to join the search.

B. The field was searched for a long time.

C. Dogs were called to look for it.

D. Both A and B.

3．Why did people keep looking for the ring even after the farm changed hands?

A. It was a very expensive ring.

B. They all wanted to do something for Nancy.

C. They all hated Nancy.

D. Everybody wanted to have this ring.

4．What did the ploughman do after finding the ring?

A. He picked it up and put it in his pocket.

B. He ran back to tell everybody else in the village.

C. He placed it to the owner.

D. He returned if to the owner.

5．What can you infer from the passage?

A. The ring was not valuable.

B. People on the farm were honest and helpful.

C. The ring's mysterious disappearance was the work of supernatural power.

D. Nancy no longer expected that her ring would be found again.

阅读理解

　　Some countries have a large number of earthquakes. Japan is one of them. Others do not have many; for example, there are few earthquakes in Britain. There is often a great noise during an earthquake. The ground shakes and houses fall down. Railway lines are broken. Trains run off the lines. Sometimes thousands of people are killed in different ways. Abut 60,000 were killed in 1783 in South Italy. A terrible earthquake in 1883 killed 35,000 people in Indonesia．

　　Another terrible earthquake happened in India in 1896. The ground suddenly moved 0.45m to one side. Then it moved back again. It moved like this 200 times a minute. Nearly all the buildings and trees fell down when that was happening.

1．________ has few earthquakes.

[　　]

2．It isn’t true that ________ during an earthquake.

[　　]

A．the ground shakes

B．materials become hot

C．some people die

D．a great noise can be heard

3．There were many fires after the Tokyo earthquake because ________ .

[　　]

A．people were using fires

B．the earthquake shook the fires

C．the houses were made of wood

D．A, B and C

4．How did the ground move when the earthquake of 1896 happened in India?

[　　]

A．It moved to one side and than back 200 times a minute.

B．It moved 0.45m to one side and then to the other side in a minute.

C．It moved 0.45m a minute

D．It moved 20 times in a minute

6．Which of the following is NOT true?

[　　]

A．Trains run off the lines because railway lines are broken during an earthquake.

B．The earthquake of 1923hit Tokyo late in the day .

C．People threw hot materials onto different parts of the houses.

D．There were few buildings in the area after the earthquake of 1896 in India．

阅读理解

阅读下列短文，从每题所给的四个选项中选出最佳选项。

　　Every animals is a living radiator (散热器)--heat formed in its cells and given off through its skin. Warm blooded animals keep a normal temperature by continuously replacing lost surface heat: smaller animals, which have more skin for every ounce of body weight, must produce heat faster than bigger ones. Because smaller animals burn fuels faster, scientists say they live faster. The speed at which an animal lives is determined by measuring the rate at which it uses oxygen. A chicken, for example, uses one-half cubic centimeters of oxygen every hour for each gram it weighs. The tiny shrew-mouse used four cubic centimeters of oxygen every hour for each gram it weighs. Because it uses oxygen eight times as fast, it is said that the shrew-mouse is living eight times as fast as the chicken. The smallest of the warm-blooded animals, the humming-bird, lives a hundred times as fast as an elephant. There is a limit to how small a warm-blooded animal can be. A mammal or bird that weighs only two and a half grams would starve to death. It would burn up its food too rapidly and would not he able to eat fast enough to supply itself more fuel.

1．The passage says that every animal is a living radiator because it _____.

[　　]

A．produces heat in its body cells

B．burns fuel to produce heat

C．sends out heat through its skin

D．takes in oxygen for burning fuel

2．Small animals are said to live faster than big ones because they _____.

[　　]

A．have more skin for their weight

B．replace lost heat faster

C．burn fuel faster than big ones

D．keep a higher body temperature

3．The amount of oxygen an animal uses depends on _____.

[　　]

A．the heat the body produces

B．the food it eats

C．its size and shape

D．the length of time it lives

4．According to the passage, which of the following inferences is possibly right?

[　　]

A．There is no limit as to how large a warm-blooded animal can be.

B．The humming-bird lives faster than any other warm-blooded animals.

C．Small animals have less skin for their body weight than large ones.

D．The humming-bird is the smallest of the warm-blooded animals.

III. 阅读理解
阅读下列短文，从每题所给的A、B、C、D选项中，选出最佳选项。
I’ve written 14 movies. My characters smoke in many of them, and they look cool and glamorous doing it. Smoking was an integral（必需的） part of many of my screenplays because I was a heavy smoker. It was part of a bad-boy image I’d cultivated for a long time— smoking, drinking, partying, rock ’n’ roll.
Smoking, I once believed, was every person’s right. The second-hand smoke was non-existent problem invented by professional do-gooders. I put all these views into my plays.
Remembering all this, I find it hard to forgive myself. I have been an accomplice (帮凶) to the murders of untold numbers of human beings. I am admitting this only because I have made a deal with God. Spare me, I said, and I will try to stop others from committing the same crimes I did.
Eighteen months ago I was diagnosed with throat cancer, the result of a lifetime of smoking. I am alive but disabled. Much of my larynx (喉) is gone. I have some difficulty speaking; others have some difficulty understanding me.
I haven’t smoked or drunk for 18 months now, though I still take it day by day and pray for help. I believe in prayer and exercise. I have walked five miles a day for a year, without missing even one day. Quitting smoking and drinking has taught me the hardest lesson I’ve ever learned about my own weakness; it has also given me the greatest affection and empathy(同感) for those still addicted.
I don’t think smoking is every person’s right anymore. I think smoking should be as illegal as heroin. I’m no longer such a bad boy. I go to church on Sunday. I’m desperate to see my four boys grow up. I want to do everything I can to undo the damage I have done with my own big-screen words and images.
Screen writers know, too, that some movie stars are more likely to play a part if they can smoke —because they are so addicted to smoking that they have difficulty stopping even during the shooting of a scene.
My hands are bloody; so are Hollywood’s. My cancer has caused me to attempt to cleanse me. I don’t wish my fate upon anyone in Hollywood, but I beg that Hollywood should stop putting it upon millions of others.
1. The main idea of this passage probably is _________.
A. the writer is ashamed of the bad effects his screenplays have had on human beings
B. the writer’s smoking experience nearly killed himself
C. the bad effects that Hollywood screenplay have brought to children
D. the determination of the writer to overcome his illness
2. How do you think the writer has realized his mistake?
A. So many people have found the habit of smoking due to his plays.
B. His plays have brought great harm to teenagers.
C. He himself suffered greatly from smoking.
D. His screenplays have been doing more and more harm to human beings.
3. What is the writer determined to do in future?
A. He has made up his mind to give up smoking forever.
B. He will try his best to prevent others from writing screen plays encouraging smoking.
C. He will try his best to bring up his four children.
D. He has decided to write his screenplays without smoking scenes.
4. It can be inferred from the passage that _______.
A. the writer will soon be recovered from his illness thanks to his exercise
B. the writer will soon die because of his deadly disease
C. smoking will be got rid of in all Hollywood films
D. smoking in Hollywood films is still doing great harm to human beings

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