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C
Things similar continuously happened in Haiti and Chile.Thousands of people were
buried in the earthquake and lost their fives.What if we could have warned them? People are always trying hard to find a way of preventing building collapsing(坍塌).Better materials and technology help,but are not a solution.Just like humans,a building has its own life circle from  “birth” to “death”.If we know when a building is going to collapse,we can repair it in advance or get out before it falls.
Now, scientists at the University of Illinois ha、,e developed a material that turns red before it breaks.The invention could be used in things like climbing ropes,or bridge supports.The secret behind the color-changing material is a type of molecule(分子).A molecule is a group of atoms held together by chemical bonds(化学键).Imagine you and your friends standing in a circle,holding hands.Each person stands for one atom,your hands represent the bonds,and the entire circle represents a molecule.If one person lets go of his or her hands,the molecule changes color.The research team put the molecule into a soft material.When the researchers stretched(拉长) the material:it turned bright red a few seconds before it broke into two pieces.
When they repeatedly stretched and relaxed the material,without breaking it,it only turned a little red.
The major problem is,light can get rid of the red color.When the team shone a bright light on the molecule,the broken bond was fixed,and the color disappeared.If bright fight keeps the red color from appearing,the material’s warning system will be useless.Scientists still have a lot of work to do before the color-changing molecule can be used outside the lab.
49.The passage is mainly about______________
A.a way of preventing building from breaking down
B.a series'-of earthquakes in Haiti and Chile
C.a way of warning before buildings collapse
D.a newly—discovered structure of a molecule
50.According to the passage,we call conclude that____________
A.there are problems to solve before putting the new material to use
B.scientists have found the life circle of buildings from “birth” to “death”
C.bright fight makes the red color visible to human eyes
D.the new material is unlikely to be used in building bridges
51.The color-changing molecule can___________
A.make building materials much stronger
B.help building materials get stretched if necessary
C.prevent the earthquake from killing people
D.remind people to leave buildings before they fall
52.The warning system is based on the fact that____________
A.red color won’t show up when it meets bright fight
B.a material with a certain type of molecule Can turn red when setched
C.a building has its own life circle of “birth”to“death”
D.the broken bond will fix itself when a molecule meets bright fight

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It seems that some people go out of their way to get into trouble.That’s more or less what happened the night that Nashville Police officer Floyd Hyde was on duty.
“I was on the way to a personal-injury accident in West Nashville.As I got onto Highway 40,blue lights and sirens(警笛)going.I fell in behind a gold Pontiac Firebird that suddenly seemed to take off quickly down the highway.The driver somehow panicked at the sight of me.He was going more than a hundred miles an hour and began passing cars on the shoulder.”
But Hyde couldn’t go after him.Taking care of injured people is always more important than worrying about speeders,so the officer had to stay on his way to the accident.But he did try to keep the Firebird in sight as he drove,hoping another nearby unit would be able to step in and stop the speeding car.As it turned out,keeping the Firebird in sight was not that difficult.Every turn the Pontiac made was the very turn the officer needed to get to the accident scene.
Hyde followed the Pontiac all the way to his destination(目的地).At that point he found another unit had already arrived at the accident scene.His help wasn’t needed.Now he was free to try to stop the driver of the Firebird,who by this time had developed something new to panic about.
“Just about that time,” Hyde said,“I saw fire coming out from under that car,with blue smoke and oil going everywhere.He’d blown his engine.Now he had to stop.”
“After I arrested him.I asked him why he was running.He told me he didn’t have a driver’s license(执照).”
That accident cost the driver of the Firebird plenty---a thousand dollars for the new engine---not to mention the charges for driving without a license,attempting to run away,and dangerous driving.
The underlined word“panicked”in Paragraph 2 means .

A.feared B.hated C.excited D.satisfied

The driver of the Firebird suddenly speeded down the highway because .

A.he was racing with another driver on the road
B.he realized he had to hurry to the accident scene
C.he thought the police officer wanted to stop him
D.he wanted to overtake other cars on the shoulder

Which of the following statements is true?

A.Someone else was taking care of the injured person.
B.The Pontiac reached its destination at the accident scene.
C.Hyde knew where he was going by following the right car.
D.The policeman was running after a speeder on Highway 40

Choose the best title for the passage.

A.Going My Way? B.Help on the Way?
C.Fun All theWay? D.Losing His Way?

So you have been called for an interview---well done?Your effort has been paid off? You will feeI better at the interview if you show an understanding of the nature of the organization.
Ask someone who already does it,or check it with one of the advisers.
Ask a member of your family or a friend to act as the employer and to give you an unreal interview.Be as realistic as possible,answer the questions seriously.Afterwards discuss how it went.Think about how the employer would prefer to see your look.Remember---the majority of employers are over 30.
It is not wise to rush out and buy new clothes.which will be worn for the first time at the interview.You’ll feel more at ease in a familiar dress.
Carelessness in any of these could cost you the job.Arrive at least 15 minutes before time,this will give you a chance to have a look around,read the notice board and get the feel of the place.Being late at the interview produces a bad impression.The first impression that the interviewer gets of you is formed as you walk through the door,so take a couple of deep breaths.
Be ready to shake hands if the interviewer offers.
Don’t take a seat until asked.Then sit comfortably.
Make eye contact when you are greeted and again if you shake hands.And during questioning,eye contact is a form of non-verbal greeting.
Remember the interviewer’s name and use it from time to time.
Be ready for the question “Is there anything you want to ask?” Before the interview you should get ready for two or three such questions.Look on these not just as a chance to get information but as a means to give your employer a better impression.Asking can show knowledge but avoid asking about holidays,pensions(养老金)and so on.It looks as if you are tired even before you begin.You can check on these later,when the hope for job is offered.
And if you fail, look upon the interview as an experience in itself.Learn from it.We wish you good luck and good job hunting.
Before you go to see the employer,you’d better .

A.find a dress you have got used to
B.buy some modern shoes,ties,etc.
C.have your hair cut
D.put on your newly-bought clothes

What does the phrase“eye contact”means?

A.A kind of greeting without words.
B.Shaking hands with the interviewer.
C.Looking at each other for a long time.
D.A way of getting a desirable job.

People usually do the following things before a job interview.Which is the right order for doing them?
a.Asking a friend to give you an unreal interview.
b.Understanding the nature of the organization.
c.Paying attention to your clothes.
d.Arriving at the place of the interview ahead of time.
e.Getting some information from the advisers.

A.a—e—b—c—d B.d—c—b—a—e
C.b—e—a—c—d D.e—d—a—b—c

Why do you prepare yourself for some Is--there·-anything·-you·-want--to-say questions?

A.To give the employer more information.
B.To get information about holiday and pension.
C.To impress the employer better and get further information from the company as well.
D.To show that you are the most knowledgeable.

Many of us believe that a person’s mind becomes less active as he grows older.But this is not true,according to Dr.Lissy F.Jarvik,professor of psychiatry(精神病学)at the University of California,Los Angeles,and a board member of the New Center for Aging at the Veterans Hospital.She has studied the mental functioning of aging persons for several years.For example,one of her studies concerns 136 pairs of twins, who were first examined when they were already 60 years old.As Dr.Jarvik continued the study of the twins into their 70s and 80s,their minds did not generally decline(下降)as was expected.
However,there was some decline in their psycho-motor(精神运动的)speed. This means that it took them longer to accomplish mental tasks than it used to.But when speed was not a factor,they lost very little intellectual (智力的) ability over the years.In general,Dr.Jarvik’s studies have shown that there is no decline in knowledge or reasoning ability.This is true not only into the 30s and 40s,but into the 60s and 70s as well.
As for learning new things,and ability to remember,studies by Dr.Jarvik and others show that the old are equal to the young.It is true that older people themselves often complain that their memory is not as good as it once was.However,much of what we call“loss of memory”is not that at a11.
In the cases where the older person’s mind really seems to decline,it is not necessarilv a sign of a decay due to becoming old or“senility”.Often it is simply a sign of a depressed emotional state.This depression usually can be got rid of by counseling(咨询)with a psychologist,or medicine which fights depression.
In American society,when an older person loses something,we tend to call him or her“senile”.But notice that when a younger person loses something,he does not blame it on senility or loss of memory.He finds some other excuse!
A long-term study of 136 pairs of twins showed that the only factor that declined over the years was .

A.mental health B.intellectual ability
C.the amount of knowledge D.psycho-motor speed

According to Dr.Jarvik’s studies,middle-aged and older persons should expect to .

A.reason better B.learn fewer new things
C.remember less D.1ose little ability to remember

The word“senility”most likely means .

A.excellent health B.weakness in body and mind because of old age
C.occasional forgetfulness D.giving up one’s life

Both younger and older persons should realize that .

A.a sign of a decay due to old age or“senility’’is a common thing
B.older persons are wiser than younger ones because of different knowledge amount
C.senility or mental decay due to aging is much less common than most of us believe
D.a sign of a depressed emotional state is not a reason of decay

More and more scientific experiments prove that physical exercise can reduce the dangers of some illnesses in middle-aged persons.Exercise strengthens the heart muscle,reduces blood pressure and help to prevent muscles from changing into fat.Physical exercise is just as important for children.
Exercise and food affect growing speed in young lab animals.Baby mice start running as soon as they are big enough to use an exercise wheel in their cage.If they get extra food and run a lot,they will grow as much as 1.5 times bigger than normal.
The same differences in growing speed might be found between active and inactive children.Physical exercise helps active children grow faster than inactive children.One experiment shows that the brains of the mice that had enough exercise weighed about 3%more than those of the mice that did not exercise The mice that exercised are much quicker to learn doing new exercise than the mice that did not exercise.
The results of the experiments suppose the theory that exercise can help babies learn to talk and walk sooner than expected.
The good effects of physical exercise are not limited to children and middle-aged people.Exercise continues to be an important part of our lives after we grow old.For example,people over 50 years old begin to lose calcium(钙) from their bones,which get weaker and can break easily.Physical exercise,however,helps to strengthen the bones and to prevent them from losing calcium.Of course,old people can take medicines to prevent themselves from suffering from losing calcium.But the medicines they take increase the chance of developing some kind of cancer(癌).So physical exercise is a much safer treatment(治疗).
From the passage we know that .

A.mice need to eat more and exercise more
B.children need more exercise than other people
C.old people like to take medicine to treat their illnesses
D.middle-aged people are easy to get fat

Active children than inactive children.

A.enjoy walking more
B.are cleverer and healthier
C.are stronger but more foolish
D.are cleverer but weaker

Why are the bones of old people easy to break according to the passage?

A.Because they are easy to become ill.
B.Because they eat less than other people.
C.Because they have less exercise than other people.
D.there is less calcium in their bones than in those of other people.

The passage tells people that .

A.only middle-aged persons can benefit from physical exercise
B.physical exercise can do good to both the middle-aged and children
C.people of different ages can all benefit from physical exercise
D.physical exercise is the safest treatment for losing calcium

In only two decades Asian Americans have become the fastest-growing US minority.As their children began moving up through the nation’s schools,it became clear that a new kind of culture was coming out.Their achievements are made in the nation’s best universities,where mathematics,science and engineering departments have taken on a decidedly Asian character.This special liking for mathematics and science is partly explained by the fact that Asian-American students who began their education abroad arrived in the U.S. with a solid grounding in mathematics but little or no knowledge of English.They are also influenced by the promise of a good job after college.Asians feel there will be less unfair treatment in areas like mathematics and science because they will be judged more objectively(客观).And the money spent on education is more immediately returned in something like engineering than with an arts degree.
Most Asian-American students owe their success to the influence of parents who are determined that their children should take full advantage of what the American educational system has to offer.An effective measure of parental attention is homework. Asian parents spend more time with their children than American parents do,and it helps.Many researchers also believe there is something in Asian culture,such as family value,the importance of education and so on that lead to their success.
Both explanations for academic success worry Asian Americans because of fears that they could cause the native Americans’unhappiness.Many can remember when Chinese,Japanese and Filipino immigrants(移民)were unequally treated because of social separation.Indeed,it was not until 1952 that laws were laid down giving all Asian immigrants the right to citizenship.
Few Asian-American students major in human sciences mainly because .

A.they are afraid they might meet with unfair judgement in these areas
B.there is a wide difference between Asian and Western cultures
C.they know little about American cultures and Western cultures
D.their English is not good enough

Asian-Americans prefer something like engineering to an arts degree because________.

A.people majoring in engineering are respected
B.people with an arts degree are looked down upon
C.they can’t find a job with an arts degree
D.they can earn more money after graduation

While making great achievements at college,Asian-American students________.

A.are afraid that their academic successes take on a strong Asian character
B.still worry about unfair treatment in society
C.generally feel it a shame to have to depend on their parents
D.feel they are mistreated because of limited knowledge of English

According to the passage,the major factors determining the success of Asian-Americans are .

A.Asian culture and the American educational system
B.Asian culture and a solid base in basic mathematics
C.hard work and parental help
D.hard work and a limited knowledge of English

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