What does fizz (氣泡) taste like? In Bubbly (多泡的)drinks such as sodas, tiny bubbles give the drink a lift--- and have a distinct taste, In a new study on mice, scientists have connected that fizzy-taste feeling to the ability to taste sourness, such as that of oranges or vinegar.
Scientists first thought the taste of bubbles came from the bubbles bursting on the tongue, but now ate starting to think differently. Charles Zuker, of Columbia University, and his team studied the nervous system of mice to understand how the tongue tastes carbon dioxide, which is the gas that makes up the bubbles.
Animals, including human beings, are able to detect different tastes by using taste buds(味蕾) which pick up tastes in the mouth, and then send them to the brain. In the experiment, different groups of mice were genetically engineered to be missing one of the senses involved in taste. “Genetically engineered” means the researchers were able to turn off the switches for certain senses by changing the genes responsible for taste. The mice in one group could not taste sweet; another, sour; the third, bitter, and the fourth, salt. When the scientists gave carbon dioxide to the mice, the nervous systems of all the mice responded to the gas, except those of the mice that could not taste sour.
This shows that the taste of the bubbles must be sour, and that by turning off the ability of the mice to taste sour, the scientists also turned off their ability to taste carbon dioxide. When they studied the cells that detect sourness, the researchers found a protein attached to the cells that is important to the process of tasting carbon dioxide. When carbon dioxide comes into contact with this protein, the protein knocks off particles called protons. These protons(質(zhì)子), in turn, travel to the brain, which says ,” Hey! That’s a taste!”
It may seem like a lot of work to get from a can of soda to a taste, but the science of the senses is anything but simple, “  Taste is a challenging system to study,” one researcher says.
小題1: What is the most important function of the bubbles?
A.To look interesting . B.To make drinks taste good.
C.To make drinks funny. D.To produce a lot of fizz.
小題2:From the experiment the researchers learned that______.
A.sourness has nothing to do with the taste of bubbles.
B.there is a connection between sourness and bubbles.
C.the taste of bubbles is better if it’s less sour.
D.most mice cannot taste carbon dioxide.
小題3: It can be inferred from the passage that ________.
A.the taste of bubbles is produced by the bubbles bursting on the tongue.
B.the nervous systems of mice show how the tongue tastes carbon dioxide.
C.taste seems simple but is very complex to research.
D.nerve cells sending signals to the brain is the first step in tasting something.
小題4: Which of the following would be the best title for the passage?
A.Nervous Systems Understand How the Tongue Tastes.
B.The Process of Taste
C.The taste of Bubbles.
D.Different Animals Detect Different Tastes.

小題1:B
小題2:B
小題3:C
小題4:C
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科目:高中英語 來源:不詳 題型:閱讀理解

In bringing up children, every parent watches eagerly the child’s acquisition of each new skill-the first spoken words, the first independent steps, or the beginning of reading and writing.It is often tempting to hurry the child beyond his natural learning rate, but this can set up dangerous feelings of failure and states of worry in the child: This might happen at any stage.A baby might be forced to use a toilet too early, a young child might be encouraged to learn to read before he knows the meaning of the words he reads.On the other hand, though, if a child is left alone too much, or without any learning opportunities, he loses his natural enthusiasm for life and his desire to find out new things for himself.
Patents vary greatly in their degree of strictness towards their children.Some may be especially strict in money matters.Others are severe over times of coming home at night or punctuality for meals.In general, the controls imposed represent the needs of the parents and the values of the community as much as the child’s own happiness.
As regards the development of moral standards in the growing child, consistency is very important in parental teaching.To forbid a thing one day and excuse it the next is no foundation for morality.Also, parents should realize that “example is better than precept”.If they are not sincere and do not practice what they teach, their children may grow confused, and emotionally insecure when they grow old enough to think for themselves, and realize they have been to some extent fooled.
A sudden awareness of a marked difference between their parents’ principles and their morals can be a dangerous disappointment.
小題1:Eagerly watching the child’s acquisition of new skills _________.
A.should be avoided
B.is universal among parents
C.sets up dangerous states of worry in the child
D.will make him lose interest in learning new things
小題2:In the process of children’s learning new skills, parents ______.
A.should encourage them to read before they know the meaning of the words they read
B.should not expect too much of them
C.should achieve a balance between pushing them too hard and leaving them on their own
D.should create as many learning opportunities as possible
小題3:The second paragraph mainly tells us that __________.
A.parents should be strict with their children
B.parental controls reflect only the needs of the parents and the values of the community
C.parental restrictions vary, and are not always intended for the benefit of the children alone
D.parents vary in their strictness towards their children according to the situation
小題4:In moral matters, parents should __________.
A.observe the rules themselves
B.be aware of the marked difference between adults and children
C.forbid things which have no foundation in morality
D.consistently ensure the security of their children

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科目:高中英語 來源:不詳 題型:閱讀理解

Providing small classes for at least several grades starting in early primary school gives students the best chance to succeed in late grades, according to groundbreaking new research from a Michigan State University scholar.
The research by Spyros Konstantopoulos, a professor of education, is the first to examine the effects of class size over a period and for all levels of students. The study appears in the American Journal of Education.
He is also a member of a group for the Department of Education’s Instiute of Education Sciences that will give official advice on class size to the states. He said the advice will mirror his research: the best plan is to provide continuous small classes(13 to 17 students) for at least several years starting in kindergarten or first grade.
“For a logn time states thought they could just do it in kindergarten or first grade for one year and get the benefits,” He said. “I don’t believe that. I think you need at least a few years in a row where all students, and especially low-achievers, receive the treatment, and then you see the benefits later.”
His research used data from the Project Star study in Tennessee that analyzed the effects of class size on more than 11,000 students in primary and middle school. He found that students who had been in small classes from kindergarten through third grade had actually higher test scores in grades four through eight than students who been in larger classes early on.
Students from all achievement levels benefited from small classes, the research found. “But low-achievers benefited the most, which narrowed the achievement gap with high –achievers in science, reading and math, ” he said.
Although the study didn’t consider classroom practices, he said the reason for the narrowing gap is likely due to low-achieving students receiving more attention from teachers.
This is especially important in poorer schools because teacher effectiveness matters more in schools with more disadvantaged and low-performing students, ” he said.
小題1:The professor argues about ________ .
A.the size of the classB.the period of the class
C.the attention from teachersD.the achievements of students
小題2:The result of the research shows that _________.
A.small classes for one year in early grade are enough
B.continuous small classes help students achieve more
C.it’s best to attend small classes in kindergarten
D.small classes do equal good to students of all levels
小題3:What can we infer from the passage?
A.High achievers will not benefit from small classes.
B.Continuous small classes have not been widely accepted.
C.Low-achievers should be separated from high-achievers.
D.Teachers’ attention matters less than classroom practices.
小題4:The underlined word “This” in the last paragraph refers to _______.
A.the gap between low and high achieversB.continuous small classes
C.classroom practices in later gradesD.the Project Star Sturdy

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科目:高中英語 來源:不詳 題型:閱讀理解

Books are not Nadia Konyk's thing. Her mother brings them home from the library, but Nadia rarely shows interest. Instead, like so many other teenagers, Nadia, 15, is addicted to the Internet. She regularly spends at least six hours a day in front of the computer, spending most of her time reading and commenting on stories written by other users. Her mother, Deborah Konyk, would prefer that Nadia read books for a change.
As teenagers' scores on reading tests have declined, some argue that the hours spent surfing the Internet are the enemy of reading—destroying a precious common culture that exists only through the reading of books. Critics have warned that electronic media would destroy reading.
Others say the Internet has created a new kind of reading. The Web inspires a teenager like Nadia, who might otherwise spend most of her leisure time watching television, to read and write. What is different now, some literacy experts say, is that spending time on the Web engages viewers with text.
Web supporters believe that strong readers on the Web may eventually surpass those who rely on books. Reading five Web sites, experts say, can be more enriching than reading one book. "It takes a long time to read a 400-page book," said Spiro. "In a tenth of the time," he said, the Internet allows a reader to "cover a lot more of the topic from different points of view."
Some literacy experts say that reading itself should be redefined. Interpreting videos or pictures, they say, may be as important a skill as analyzing a novel or a poem. "Kids are using sound and images so they have a world of ideas to put together," said Donna Alvermann, a professor of literacy education at the University of Georgia. "Books aren't out of the picture, but they're only one way of experiencing information in the world today."
Next year, the Organization for Economic Cooperation and Development, which gives reading, math and science tests to 15-year-old students in more than 50 countries, will add an electronic reading component(軟件). The United States says it will not participate because an additional test would overburden schools.
小題1:Why are books not the thing of Nadia Konyk?
A.She does reading mainly through electronic media.
B.Her mother doesn’t provide her with enough books.
C.She has become addicted to playing games on the web.
D.Like many youngsters, she has lost interest in reading.
小題2:How many hours does Nadia spend in front of the computer in a week?
A.Exactly forty-two hoursB.Usually fifty hours
C.More than forty hoursD.At most thirty-six hours
小題3:Which of the following statements is correct according to the passage?
A.To search for information on the web engages viewers without text.
B.To explain videos is a technique more important than analyzing a novel.
C.Children using sound and images may lose their interest in movies.
D.People reading well online may surpass those who rely on books.
小題4:Why did the US refuse to participate in the tests with an added electronic reading component?       It is because ______.
A.the teachers and students considered it useless
B.such a test would give schools more extra work
C.they thought reading was the only way to get information
D.none of them showed interest in such an additional test

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科目:高中英語 來源:不詳 題型:閱讀理解

COOL INVENTIONS




From school to band Practice, the Venturi Eclectic is an Earth-friendly way to get Where you want to go.This battery-powered, zero-emission (meaning it doesn't pollute the air) vehicle runs mainly on renewable energy.Solar panels on the Eclectic's roof absorb sun rays when you're driving.On windy days, you can connect a machine to the car's roof that collects energy from the wind while you're parked.The Eclectic's top speed is 28 miles an hour; the battery lasts for 31 miles before it needs to be recharged.Zipping (迅速行進(jìn)) around the neighborhood has never been better.
Here's an eco-friendly way to tell time: Simply fill the Bedol Water-powered Clock's tank (箱) with water, add some lemon juice, and the clock will display the time without the need for environmentally harmful batteries.There are two sets of metal electrodes (電極) inside the water tank.Water contains ions (離子) that carry negative and positive charges.These ions complete a charge between the electrodes, creating enough energy to power the clock.Just refill the tank every few weeks, and this clock will keep on ticking.
Bloodhound SuperSonic Car (SSC) will be the first car to attempt to break the l,000-mile-an-hour barrier.(The current record is 763 miles an hour.) A concept for now, the rocket-shaped car gets its initial push to 350 miles an hour from a jet engine.Then a rocket fires up, pushing the SSC past 1,000 miles an hour.In order to keep the car streamlined (流線型的), the driver lies back at a 45-degree angle.
You're having a blast at your friend's birthday party.But when it's time to bring out the cake, everyone crowds around, blocking your view.No worries.Throw the Triops into the air, and this clever camera captures the view from above.The Triops can take three pictures at once, each from different angles.You can also record sounds and command the Triops to start shooting whenever it hears that noise.That's one smart camera.
小題1:According to the passage, the Venturi Eclectic      .
A.is popular with businessmenB.is suitable for a long trip
C.can turn wind into energyD.has only a little gas emission
小題2:What is the common characteristic of the Venturi Eclectic and the Bedol Water-powered Clock?
A.They don't need batteries.B.They are difficult to operate.
C.They can be powered by water.D.They are environmentally friendly.
小題3:The underlined phrase “having a blast” in the last paragraph probably means      .
A.looking at a pictureB.enjoying yourself
C.blowing out a candleD.recording sounds
小題4:Which of the following is TRUE according to the passage?
A.The Triops is sensitive to sounds.
B.The driver of the SSC must be of great size.
C.The color of the Bedol Water-powered Clock is like that of lemon.
D.The SSC doesn’t have anything to do with a rocket actually.

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科目:高中英語 來源:不詳 題型:閱讀理解


B
China is going green.In order to reduce air pollution and oil shortages, carmakers have announced their plans to develop hybrid vehicles (混合燃料汽車) for the Chinese market.Toyota’s hybrid car Prius will be ready to drive in China this week.Let’s have a look at the new car.
Any vehicle is a hybrid run on a rechargeable battery and gas.Hybrid cars have special engines, which are smaller than traditional gas engines.The gasoline engine provides 99 percent of the power when the car is going at a steady speed. A specially designed battery motor provides extra power for running up hills or when it needs to speed up.
Step into a Prius, and turn on the engine.The first thing you notice is that it is quieter than a traditional car.At this point, the car’s gas engine is at rest.The electric motor will provide power until the car reaches about 24km/h.If you stay at a low speed, you are effectively driving an electric car, with no gas being used, and no waste gas given off.
The computer decides when to use the gas engine, when to go electric, and when to use a combination of the two.If you go over 24km/h, when you step on the gas pedal (油門), you are telling the computer how fast you want to go.
The electric motor recharges automatically using a set of batteries.And when driving at a high speed, the gas engine not only powers the car but also recharges the batteries.When you use the brake, the electric motor in the wheels will work like a generator (發(fā)電機(jī)) to produce electricity to recharge the batteries.As a result, the car’s batteries will last for around 200,000 miles.
66.The underlined sentence probably means ________.
A.there will be more and more green land in China  
B.China’s new cars are combinations of different green models
C.China is still young and lacking in experience
D.the environment is getting better in China
67. What is the most important feature of hybrid cars?
A. They are powered by both a rechargeable battery and gas.
B. They have smaller engines than traditional gas ones.
C. They only use 99 percent of their power to run up hill.
D. They are much quieter than traditional cars.
68. We can know from the story that ________.
A. the gas engine recharges the batteries as well as powering the car
B. using the brake suggests that the gas engine should work
C. the car’s batteries will last for around 200,000 miles without being recharged
D. the batteries can be recharged at any time you want
69. The author writes the passage mainly to________.
A. announce plans to develop hybrid vehicles for the Chinese market
B. let people know how to save their gas when driving a car
C. teach people how to drive a hybrid car
D. introduce a new kind of “green” car
70.Which of the following statements is TRUE according to the text?
A.The hybrid car is environmentally friendly.
B.The hybrid car is unable to get itself recharged.
C.The hybrid car has been made in mass.
D.The hybrid car can decide what power to use

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科目:高中英語 來源:不詳 題型:閱讀理解


ALBANY,New York—Students who rely on working at night to improve their
grades might want to sleep on that strategy: A new survey in the US says those who never study all night have slightly higher grades than those who do.
A survey of 120 students at St.Lawrence University found that students who had never pulled an all­nighter on average had higher grades than those who had. The survey found those who did not study through the night had a grade point average of 3.2 compared to 2.95 for those who did.
The study, by assistant professor of psychology Pamela Thacher, is to be included in the January issue of Behavioral Sleep Medicine.
“It's not a big difference,but it's pretty striking, ” Thacher said, “I am primarily a sleep researcher and I know nobody thinks clearly at 4∶00 in the morning. You think you can do,but you can't.”
Many college students, of course, have inadequate or irregular sleep, for reasons ranging from excessive caffeine to poor time management.
“A lot of students were under the impression that all­nighters were a very useful tool for accomplishing work, and that caffeine intake was very useful in meeting deadlines and stuff like that, ”said Mr Chatani, who had a 3.4 grade point average last term.
Dr Howard Weiss, a physician at St.Peter's Sleep Center in Albany, said the study results made sense.
“Certainly that data is out there showing that short sleep duration absolutely interferes with concentration and performance on objective testing, ”he said.
“Some night owls do get good grades, of course,which may be explained by circadian (晝夜節(jié)律的,生理節(jié)奏的) rhythms, ”Weiss said, “Some people have different 24­hour body clocks from others, and may do better depending on classes and testing time.”
63.The purpose of the passage is to tell us     
A. the bad effects of pulling an all­nighter
B. pulling an all­nighter leads to sleep problems
C. Thacher's doubt about all­nighters
D. all­nighters influence students' grades
64. According to Thacher's study,around 4 o'clock in the morning is a time when     .
A. one can think more clearly
B. one has his/her best memory
C. one can't learn efficiently
D. one's brain falls into a period of deep sleep
65.What can we know from Dr Howard Weiss' words?
A. Thacher's study is not convincing enough.
B. He believes in Thacher's study.
C. Thacher's study makes no sense.
D. Thacher should take exceptions into consideration.

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科目:高中英語 來源:不詳 題型:閱讀理解

New technology links the world as never before. Our planet has shrunk(收縮). It’s now a “global village” where countries are only seconds away by fax or phone or satellite link. And, of course, our ability to benefit from this high-tech communication’s equipment is greatly enhanced by foreign language skills.
Deeply involved with this new technology is a breed of modern businesspeople who have a growing respect for the economic value of doing business abroad. In modern markets, success overseas often helps support domestic(國內(nèi)的) business efforts.
Overseas assignments are becoming increasingly important to advancement within executive(行政的) ranks. The executive stationed in another country no longer need fear being “out of sight and out of mind.” He or she can be sure that the overseas effort is central to the company’s plan for success, and that promotions often follow or accompany an assignment abroad. If an employee can succeed in a difficult assignment overseas, superior will have greater confidence in his or her ability to cope back in the United States where cross-cultural considerations and foreign language issues are becoming more and more common.
Thanks to a variety of relatively inexpensive communications devices with business applications, even small businesses in the United States are able to get into international markets.
English is still the international language of business. But there is an ever-growing need for people who can speak another language. A second language isn’t generally required to get a job in business, but having language skills gives a candidate(候選人) the edge when other qualifications appear to be equal.
The employee posted abroad who speaks the country’s principal language has an opportunity to fast-forward certain negotiations, and can have the cultural insight to know when it is better to move more slowly. The employee at the home office who can communicate well with foreign clients(客戶) over the telephone or by fax machine is an obvious asset to the firm.
小題1:What is the author’s attitude toward high-tech communications equipment?
A.Critical.B.Indifferent.C.Negative.D.Positive.
小題2:With the increased use of high-tech communications equipment, business people_________.
A.have to get familiar with modern technology
B.a(chǎn)re gaining more economic benefits from domestic operations
C.a(chǎn)re placing more importance on their overseas business
D.a(chǎn)re eager to work overseas
小題3: In this passage, “out of sight and out of mind” (Para. 3) probably means _________.
A.being unable to think properly for lack of insight
B.being totally out of touch with business at home
C.missing opportunities for promotion when abroad
D.leaving all care and worry behind
小題4:According to the passage, what is an important consideration of international corporations in employing people today?
A.Connections with businesses overseas.B.Ability to speak the client’s language.
C.Technical know-how.D.Business experience.

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科目:高中英語 來源:不詳 題型:閱讀理解


The magnitude 7.9 quake struck Sichuan province on May 12 at around noontime, which may have increased the human death toll because many people were at school, and the school buildings turned out to be not firm enough to collapse because of poor construction. More than 69,000 people have been confirmed dead so far, and more than 374,000 injured, with fears of further disasters because several lakes created by rockfall dams may give way and cause sudden flooding.
Clark Burchfiel, Schlumberger Professor of Geology, and Leigh Royden, professor of geology and geophysics in the Department of Earth, Atmospheric and Planetary Sciences at MIT, have been doing extensive research in that region of China and the Tibetan plateau(高原) for more than two decades, but had found no signs that suggested such a large earthquake might strike the area.
The team operated 25 broadband seismograph (地震儀) stations in this region of western Sichuan for more than a year. "Nobody was thinking there would be a major earthquake in that area," Royden says. "This earthquake was quite unusual, and may have involved a simultaneously(同時發(fā)生的) severe break of two separate but neighboring faults," she continued.
The region is extremely unusual geologically, Royden says, because of the very steep slopes at the boundary between the Sichuan Basin to the east and the Tibetan plateau to the west. The altitude rises sharply by about 3,500 meters (more than two miles) over a span of only about 50 kilometers (about 30 miles).
The area where the quake occurred is part of the boundary between two of the Earth's structural plates, where the Indian and Asian plates meet in an ongoing collision that has created the Himalayan mountains and the Tibetan plateau. But in central and eastern Tibet, unlike most other areas of continental collision, much of the movement of crust(地殼) is hidden from view. Instead of thickening the entire crust by folding and faulting, the surface of the eastern Tibetan plateau is not deformed(變形的) and is being lifted upward by thickening of a weak crustal layer more than 15 km below the surface.
60. Why did the school buildings collapse in the earthquake, according to the passage?
A. They had too long a history.
B. They were poorly built.
C. They were crowded with students and teachers.
D. They were damaged by the earthquake.
61. Based on Para. 1, why does the writer think that more people will be killed or injured after 
the earthquake?
A. Because there will be more aftershocks after the major quake.
B. Because more school buildings will collapse after the quake.
C. Because destructive flooding caused by rockfall dams is likely to occur..
D. Because there was not enough medical care for the injured in the area.
62. What can we infer from this passage?
A. There was no prediction that such a large-scale quake might occur there.
B. Researchers had done little research in that area before the earthquake struck it.
C. The 5.12 earthquake was the most destructive in the world.
D. If more research had been done, the destruction could have been avoided.
63. Which one can be used as the best title for this passage?
A. The Great Disasters.
B. The Earthquake was very frightening.
C. The Causes of the earthquake.
D. An Extremely Unusual Earthquake.

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