Mothers have known it for years. Give the children a hamburger, and they will love it; spend hours making a home-cooked meal, and they will leave it on the plate. Now French scientists have discovered why. According to researchers near Paris, the brain does not respond well to unfamiliar tastes. Sensations are not as strong when the mind is struggling to understand messages that come from the tongue. This provides little reason to taste new things.Human beings are naturally like rats – we are afraid of anything new. If you give rats some food that they have never had before, they will turn their backs on it out of fear. We are the same. It is possible to introduce new foods, but only in the right psychological context, like a birthday. Once the introduction has been made, the fact of having a full stomach is physically pleasing, so the next time it is easier. However, some foods are more tempting than others. Scientists are sure that we are born with a sweet tooth. This is why children have a natural desire for sugar.Another discovery is how a sense of smell affects our appetite. In one experiment, chemical substances were put on the tongues of human participants. At the same time, air was blown down the participants’ noses so they could not smell the chemical substances. As a result, no two people got the same sensation from the same food. Physical, psychological, and cultural differences shaped the response.The intensity of feelings about food depends upon knowledge of it. The average student who eats a new dish will have only a cloudy image of it, but for some people whose tongues are trained to appreciate fine differences, they’ll have an exciting experience, much like someone who has a great musical ear. This is why someone who eats hamburgers everyday likes them and becomes a hamburger expert. They can tell the difference between a Big Mac and a Burger King, just like the Japanese can tell the difference between varieties of rice that taste the same to Europeans.21. Why do children prefer a hamburger to a home-cooked meal?

第1题

I would go and inform him if I（）his address.

A.had known

B.knew

C.would have known

D.know

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第2题

Which of the following sentences is INCORRECT？A．I suppose he ought to have known that, don

Which of the following sentences is INCORRECT？

A．I suppose he ought to have known that, don"t I？

B．He seldom gives his wife a gift, does he？

C．There won"t be any trouble, will there？

D．No one would object, would they？

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第3题

Since ancient times, the value of chicken soup______A．has been over-estimatedB．has been wi

Since ancient times, the value of chicken soup______

A．has been over-estimated

B．has been widely acknowledged

C．has been appreciated only by philosophers

D．has been known only to mothers

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第4题

Man: Someone said that there was a really good documentary on television last night about

killer whales. I wish I had seen it since that was what we were studying in my zoology class.

Woman: I'm sorry. If I had known you were interested in that sort of thing I would have told you when it was going to be on.

Question: What does the woman imply？

A．She didn't watch the program.

B．She is not usually interested in watching documentaries.

C．She doesn't have time to help the man with his project.

D．She knew that the program was being shown.

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第5题

Itis not until you have lost your health ______ yo

u know its value.

A. until B.when C. what D. that

3. He talks as if he _______everything in the world.

A．knows B．knew

C．had known D. would have known

4. Never before _______ seesuch a terrible car accident on the road!

A. I have B.have I C. I did D. did I

5. The girl sometimes hasdif6culty _________ what the teacher says in class.

A．understand B．understanding

C．to understand D．understood

6. The paint is still wet._________.

A．Be not sure to touch it! B．Be sure not to touch it!

C．Be sure to not touch it! D．Don't be sure to touch it1

7. The students ______ theirpapers by the end of this month.

A．have finished B．will be finishing

C．will have finished D．have been finishing

8. —Did the medicine make you feel better？

—No. The more ________, ________ I feel.

A. medicine I take; and the worse B. medicine I take; the worse

C. I take medicine; the worse D. I take medicine; worse

9. There was so much noise inthe classroom that the teacher couldn't make himself ______.

A. heard B.hearing C. to hear D. hear

10. This overcoat cost_________. What's more, they are _______ small for me.

A. very much; very B.too much; much too

C. much too; too much D. very much; too much

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第6题

Most Americans think that ice cream is as American as baseball and applepie.But ice cr

eam was known long before American was discovered.The Roman emperor Nero may have made a king of ice cream.He hired hundreds of men to bring snow and ice from the mountains.He used it to make cold drinks.Traveler Marco Polo brought back recipes for chilled and frozen milk from China.Hundreds of years later,ice cream reached England.It is said that King Charles I enjoyed that treat very much.There is a story that he bribed his cook to keep the recipe for ice cream a royal secret.Today ice cream is known throughout the world.Americans alone eat more than two billion quarts a year.

Charles I of England wanted to ()

A、make ice cream popular

B、keep the secret of ice cream for himself

C、develop new kinds of ice cream

D、bring ice cream recipes from China

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第7题

Some students at the Open University left school 20 years ago. Others are younger but

all must be at least 21 years old. This is one example of how the Open 3 University is different from all other universities. Its students must either work full-time or be at home all day. For instance, mothers of families do not have to pass any examinations before they are accepted as students. This is why the university is called “open”. The university was started in order to help a known group – people who missed having a university education when they were young.

The first name for the Open University was “the University of the Air”. The idea was to teach “on the air”, in other words on radio and television. Most of the teaching is done like this. Radio and television have brought the classroom into people’s homes. But this, on its own, is not enough for a university education. The Open University students also receives advice at one of 283 study centers in the country, 36 weeks of the year he or she has to send written work to a “tutor”, the person who guides his or her studies. The student must also spend 3 weeks every summer as a full-time student. Tutors and students meet and study together, as in other universities.

1. The purpose of the Open University is to ().

A. help the young to go to school

B. help those who want to study the university

C. help those who are younger than 21 years old

D. help those who had missed the chance to study when they were young

2. “On the air” means ().

A. on the show

B. on radio and TV

C. on the flight

D. flying everywhere

3. The students at the Open University have their education ().

A. both at home and at some study centers

B. through many kinds of examinations

C. with their written work only

D. in the local centers only

4. “Tutor” in the second paragraph means ().

A. the person who is in charge of various exams

B. the person who is to help students get through exams

C. the person who provides guidance to students in their studies

D. the person who teaches students face to face

5. Which of the following is implied but not stated？ ()

A. Everyone wants to go to such an open university

B. Every country needs such a university

C. Students must be over 21 years old in the Open University

D. The Open University really benefits a lot those who did not have the chance to have university education

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第8题

The largest shark known to us, Megalodon, is extinct. Or is it？ Carcharodon Megalodon, com

monly known as Megalodon, is believed to have lived between I million and 5 million years ago and thought to have been 52 feet long. It is (or was) a shark that had a jaw 7 or more feet wide. Fairly recently, there has been some speculation about whether it is extinct or just out of reach. But few people believe that Megalodon has found a home deep in the ocean.

There are many known "Living Fossils": Coelacanth, Sea Cucumbers, Sea Urchins, Lobsters, Sea Stars. The common ones like lobsters and sea urchins are not really looked on as anything amazing. They've been around for thousands of years or more, and axe easily accessible to us. What if they weren't accessible and yet still existed？ We would label them extinct. The discovery of a live Coelacanth, a fish long believed extinct, challenged some scientists' long-held beliefs on extinction. There have been recent discoveries Of incredibly large squid, and deep-sea fish never before seen by scientists.

In the 1960s the U.S. Navy set up underwater microphones around the world to track Soviet submarines. The network, known as the Sound Surveillance System, still lies deep below the ocean's surface in a layer of water known as the "deep sound channel'. The temperature and pressure of the channel allow sound waves to travel undisturbed. NOAA's Acoustic Monitoring Project has been using the Sound Surveillance System to listen for changes in ocean structure like ocean currents or volcanic activity. Most of the sounds recorded are common and of no concern. One sound, identified in 1977 by U.S. Navy "spy" sensors, was odd. It was obviously a marine animal but the call was more powerful than any of the calls made by any other reported sea creature. It was too big for a whale. Could it be a deep-sea monster？ One possibility was a giant squid, but no one is sure. It was named "Bloop". Could it be Megalodon？ If Megalodon is still alive down in the bottom of the ocean, we may some day soon discover it. Then what？ Deep sea diving will never be the same, that's for sure!

The following is commonly known EXCEPT ________.

A．Megalodon, the largest shark, is extinct

B．Megalodon is not extinct but just out of reach

C．Megalodon was 52 feet long and had a jaw 7 or more feet wide

D．Megalodnn lived between several million years ago

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第9题

Part ADirections :Read the following three texts. Answer the questions on each text by' ch

Part A

Directions :

Read the following three texts. Answer the questions on each text by' choosing A, B, Cor D. Mark your answers on，ANSWER SHEET1.

Text 1

Whenever Catherine Brown, a 37-year-old journalist, and her friends, professionals in their 30s and early 40s, meet at a London cafe, their favorite topic of conversation is relationships: men's reluctance to commit, women's independence, and when to have children-or, increasing-Iy， whether to have them at all. "With the years passing my chances of having a child go down, but I won't marry anyone just to have a child," says Brown. To people like Brown, babies are great-if the timing is right. But they're certainly not essential.

In much of the world, having kids is no longer a given. "Never before has childlessness been an understandable decision for women and men in so many societies," says Frank Hakim at the London School of Economics. Young people are extending their child-free adulthood by postponing children until they are well into their 30s, or even 40s and beyond.

A growing share are ending up with no children at all. Lifetime childlessness in western Germany has hit 30 percent among university-educated women, and is rapidly rising among lower-classmen. In Britain, the number of women remaining childless has doubled in 20 years.

The latest trend of childlessness does not follow historic patterns. For centuries it was not unusual for a quarter of European women to remain childless. But in the past，childlessness was usually the product of poverty or disaster, of missing men in times of war. Today the decision to have-or not have-a child is the result of a complex combination of factors, including relationships, career opportunities, lifestyle. and economics.

In some cases childlessness among women can be seen as a quiet form. of protest. In Japan, support for working mothers hardly exists. Child care is expensive, men don't help out, and some companies strongly discourage mothers from returning to work. "In Japan, it's career or child，"says writer Kaori Haishi . It's not just women who are deciding against children; according to a re-cent study, Japanese men are even less inclined to marry or want a child. Their motivations, though, may have more to do with economic factors.

46. Catherine Brown and her friends feel that having children is not _________

[ A] totally wise

[ B] a huge problem

[ C] a rational choice

[ D ] absolutely necessary

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第10题

The reason some children are backward in speaking today is that （）.

A.they do not listen carefully to their mothers.

B.their brains have to absorb too much language at once.

C.their mother do not respond to their attempt to speak.

D.their mothers are not intelligent enough to help them.

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第11题

The economy started 2006 extremely strong in spite of record oil prices and rising interes

t rates. An unusually mild winter across much of the country is part of the story, but the lack of worry by consumers and business about oil prices is an even bigger part. The question remains, will we continue to glide down the economic highway or slip on oil？

Oil prices have raised overall consumer prices and cut into household purchasing power. So far the higher costs haven't deterred(阻止) buying, even buying of cars and other energy-sensitive items. The major reason for the lack of reaction is that oil is less important to the economy than it once was. Oil, which produced 45% of world energy in 1971, accounted for only 35% in 2003, with increases in nuclear and natural gas use making up the difference.

GM, Ford, and Chrysler suffered as buyers shifted to more fuel-efficient vehicles from Toyota and Honda, but the shift was hot pronounced. Admittedly, light truck sales are holding up in part because manufacturers are offering large discounts to "move the metal", but the fact that buyers are responding to those incentives shows they aren't too scared of gas prices.

Americans continue to spend more than they earn, but gasoline prices will have an effect. Although the April chain store results suggest gasoline prices aren't hurting much yet, eventually Americans will be forced to realize that they have to slow down. We expect the economy to slow in the second half of the year as the impact of higher oil prices sinks in. How much the economy slows will depend on how high oil prices remain. We expect some drop in oil prices by yearend, but I have been saying that for so long even I am starting not to believe it.

The anger against the oil companies is clearly misplaced. Exxon and friends control only a small share of world oil reserves. Most are now in the hands of state-owned oil companies. The recent move by Bolivia to nationalize its industry is only the latest in a long line of similar actions. The history of these enterprises is one of severe underinvestment and mismanagement, which tends to reduce supply and keep prices high. The risk on oil prices is primarily on the high side of our forecast.

Although I think oil prices will drop back in the medium term, to address my serious worries, I'm buying my wife a bike for Mothers' Day.

The economy at the beginning of 2006 is not affected by the high oil price mainly because ______.

A．the warm winter requires less oil to run the heaters

B．the warm winter promotes consumption, across the country

C．people believe that the oil price will drop in near future

D．people don't think the high price will make much of a difference

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