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Have you ever wondered why birds sing? Maybe you thought that they were just happy．After all, you probably sing or whistle when you are happy．
Some scientists believe that birds do sing some of the time just because they are happy．However, they sing most of the time for a very different reason．Their singing is actually a warning to other birds to stay out of their territory．
Do you know what a "territory" is? A territory is an area that an animal, usually the male, claims as its own ．Only he and his family are welcome there ．No other families of the same species are welcome．Your yard and house are your territory where only your family and friends are welcome．If a stranger should enter your territory and threaten you, you might shout．Probably this would be enough to frighten him away．
If so, you have actually scared the stranger away without having to fight him．A bird does the same thing．But he expects an outsider almost any time, especially at nesting （筑巢） season．So he's screaming （高聲尖叫） all the time, whether he can see an outsider or not．This screaming is what we call a bird's song, and it is usually enough to keep an outsider away．
Birds sing loudest in the spring when they are trying to attract a mate and warn others not to enter the territory of theirs．You can see that birds have a language of their own．Most of it has something to do with attracting mates and setting up territories．
【小題1】Some scientists believe that most of the time birds' singing is actually

A．a(chǎn)n expression of happiness

B．a(chǎn) way of warning

C．a(chǎn)n expression of anger

D．a(chǎn) language of their own

【小題2】What is a bird's "territory"?

A．A place where a bird may shout at the top of its voice．

B．A place where other bird families are not accepted．

C．An area for which birds fight against each other．

D．An area which a bird considers to be its own

【小題3】Why do birds keep on singing at nesting season?

A．Because their singing helps frighten outsiders away．

B．Because their singing helps get rid of their fears．

C．Because they want to find outsiders around．

D．Because they want to invite more bird friends．

【小題4】How does the writer explain birds' singing?

A．By comparing birds with human beings．	B．By reporting experimental results．
C．By describing birds'daily life．	D．By telling a bird's story．

We had known for along time that flowers of different plants open and close at different time of day. Yet no one really understands why flowers open and close like this at special time. The question is not as simple as we might think, as recent experiments have shown. In one experiment, flowers were kept in constant (持續(xù)的）darkness. We might expect that the flowers ,without any information about the time of the day, did not open as they usually do. In fact, they continue to open at their usual time. This shows that they have some special ways of knowing the time. Their sense(感覺) time does not depend on information from the outside world. It is inside them: a kind of "inner (內(nèi)部的）clock". This discovery may not seem to be very important. However, it is later found that not just plants but animals have this "inner clock" which control（控制）the working of their bodies and influences their activities. Human beings, then, are also influenced by it. Whether we wish or not, itaffectssuch things in our life as our need for sleep or need for food.
【小題1】Before the experiment arrived at a conclusion, people had thought that the flowers would____.

A．never open in constant darkness

B．change their usual time to open

C．open ahead of the time as they usually did

D．continue to open at usual time

【小題2】The sense of time that flowers have is connected with_____________.

A．its age and size

B．light and temperature

C．a(chǎn) kind of strange power(力量）inside them

D．some unknown information from the outside world

【小題3】What will happen if we make good use of the "inner clock"

A．We'll need less sleep or food.

B．We'll be able to sleep as long as we wish to.

C．We'll be able to change our work time when necessary.

D．We'll have more energy to do our work better.

【小題4】What's the Chinese meaning of the underlined word" affects"

A．產(chǎn)生

B．影響

C．給予

D．依賴

Autumn blues? Let the sunshine in falling leaves, flowers, and cold winds. For many people late autumn can be a season of depression.
Those who suffer from “ the autumn blue” are often extremely tired, lack energy, need more sleep, feel increased appetite and gain weight. "The exact cause of this condition, often called seasonal depression or seasonal affective disorder (SAD), is not known yet," says Chen Jue, associate professor at Shanghai Mental Health Center. "But recent studies indicate that weather change is influential and strongly suggest that this condition is caused by changes in the availability(得到) of sunlight."
One theory is that with decreased exposure to sunlight, the biological clock that regulates mood, sleep, and hormones is delayed, running more slowly in winter. Exposure to light may reset the biological clock. Another theory is that brain chemicals that transmit information between nerves, called neurotransmitters (for example, serotonin), may be altered in individuals with SAD. It is believed that exposure to light can correct these imbalances. "It is a sad season, but you can try to make it happy. Remember, spring always lives in your heart," Chen says. “Going outdoors to get some sunlight may reduce the tension that brings you the low spirits. Relax at work. Stretch, breathe deeply. Take a tea break. Think of your next vacation. Color treatment also works in handling low mood. Music also plays a role in treating autumn blues.”
【小題1】Autumn blues is also called autumn________.

A．depression

B．sunshine

C．blue music

D．cold winds

【小題2】From the 3rd paragraph we know that there _______ that can help to deal with autumn blues.

A．is no biological clock	B．is a real example
C．is no possibility	D．a(chǎn)re some ways

【小題3】Which of the following is true according to the text?

A．The real cause for autumn blues is still unknown.

B．Autumn blues can be feelings of happiness.

C．People feel tired in autumn.

D．Weather doesn’t change people.

【小題4】Which of the following CAN’T you do in order to deal with autumn blues?

A．Reset the biological clock regulating mood, sleep and hormones.

B．Eat more food very low in calories and sugar.

C．Keep the balance of nerves that transmit information.

D．Take outdoor activities or sports.

Since ancient times, people have known about its ability to reduce pain and high body temperature. More than 2000 years ago, the Greek doctor Hippocrates advised his patients to chew on the bark and leaves of the willow.
The tree contains a chemical called salicin（柳醇）. From salicin, researchers in the 1800s discovered how to make salicylic acid（酸）. And in 1897, a chemist named Felix Hoffmann at Friedrich Bayer and Company in Germany created acetyl salicylic acid. Later it became the active substance in a new medicine that Bayer called aspirin. The "a" came from acetyl. The "spir" came from the spirea plant, which also produces salicin. And the "in" Well, that is a common way to end medicine names.
In 1982, a British scientist shared the Nobel Prize in Medicine in part for discovering how aspirin works. Sir John Vane found that aspirin blocks the body from making natural substances called prostaglandins（前列腺素）.Prostaglandins have several effects on the body. Some cause pain and the expansion, or swelling（ 腫瘤; 膨脹）, of damaged tissue. Others protect the lining of the stomach and small intestine. Prostaglandins also make the heart, kidneys and blood vessels （血管）work well. But there is a problem. Aspirin works against all prostaglandins, good and bad. Scientists learned how aspirin interferes with an enzyme（酶）. One form of this enzyme makes the prostaglandin that causes pain and swelling. Another form of the enzyme creates a protective effect. So aspirin can reduce pain and swelling in damaged tissues. But it can also harm the inside of the stomach and small intestine（腸）.
【小題1】What sickness can the medicine from the willow deal with according to the passage?

A．Cold

B．Toothache

C．Cancer

D．Skin disease

【小題2】What can we know about Prostaglandin according to the passage?

A．It results from pain.

B．It prevents the lining of the stomach and small intestine.

C．It causes blood vessels to work wrongly.

D．It is sometimes good but sometimes bad.

【小題3】What can we know about aspirin according to the passage?

A．Aspirin can treat almost diseases.

B．Aspirin can create the protective enzyme.

C．Aspirin can harm the inside of the stomach and small intestine.

D．Aspirin can protect the inside of the stomach and small intestine.

The need to feed a growing population is putting much pressure on the world's supply of water. With 97% of the world's water too salty to be drunk or used in agriculture, the worldwide supply of water needs careful management, especially in agriculture. Although the idea of a water shortage(短缺)seems strange to someone fortunate enough to live in a high rainfall country, many of the world's agricultural industries experience constant water shortages.
Although dams can be built to store water for agricultural use in dry areas and dry seasons, the costs of water redistribution(重新分配)are very high. Not only is there the cost of the engineering itself, but there is also an environmental cost to be considered. Where valleys(山谷)are flooded to create dams, houses are lost and wildlife homes destroyed. Besides, water may flow easily through pipes to fields, but it cannot be transported from one side of the world to the other. Each country must therefore rely on the management of its own water to supply its farming requirements.
This is particularly troubling for countries with agricultural industries in areas dependent on irrigation (灌溉). In Texas, farmers' overuse of irrigation water has resulted in a 25% reduction of the water stores. In the Central Valley area of southwestern USA, a huge water engineering project provided water for farming in dry valleys, but much of the water use has been poorly managed.
Saudi Arabia's attempts to grow wheat in desert areas have seen the pumping of huge quantities of irrigation water from underground reserves. Because there is no rainfall in these areas, such reserves can only decrease, and it is believed that fifty years of pumping will see them run dry.
【小題1】What is most likely to be discussed in the paragraph that follows?

A．Ways to reduce the costs of building dams.

B．Steps to improving water use management.

C．Measures to deal with worldwide water shortages.

D．Approaches to handling the pressure on water supply.

【小題2】From the first two paragraphs we learn that________.

A．much of the world's water is available for use

B．people in high rainfall countries feel lucky

C．the costs of water redistribution should be considered

D．water can be easily carried through pipes across the world

【小題3】The text is mainly about________.

A．water supply and increasing population

B．water shortages and environmental protection

C．water redistribution and wildlife protection

D．water use management and agriculture

Why play games? Because they are fun, and a lot more besides. Following the rules… planning your next move…acting as a team member… these are all “game” ideas that you will come across throughout your life.
Think about some of the games you played as a young child, such as rope-jumping and hide-and-seek. Such games are entertaining and fun. But perhaps more importantly, they translate life into exciting dramas that teach children some of the basic rules they will be expected to follow the rest of their lives, such as taking turns and cooperating.
Many children’s games have a practical side. Children around the world play games that prepare them for work they will do as grown-ups. For instance, some Saudi Arabian children play a game called bones, which sharpens the hand-eye coordination (協(xié)調(diào)) needed in hunting.
Many sports encourage national or local pride. The most famous games of all, the Olympic Games, bring athletes from around the world together to take part in friendly competition. People who watch the event wave flags, knowing that a gold medal is a win for an entire country, not just the athlete who earned it. For countries experiencing natural disasters or war, an Olympic win can mean so much.
Sports are also an event that unites people. Soccer is the most popular sport in the world. People on all continents play it — some for fun and some for a living. Nicolette Iribarne, a Californian soccer player, has discovered a way to spread hope through soccer. He created a foundation to provide poor children with not only soccer balls but also a promising future.
Next time you play your favorite game or sport, think about why you enjoy it, what skills are needed, and whether these skills will help you in other aspects of your life.
【小題1】Through playing hide-and-seek, children are expected to learn to ________.

A．be a team leader

B．obey the basic rules

C．a(chǎn)ct as a grown-up

D．predict possible danger

【小題2】The underlined part in Paragraph 2 most probably means that games can ________.

A．describe life in an exciting way

B．turn real-life experiences into a movie

C．make learning life skills more interesting

D．change people’s views of sporting events zxxk

【小題3】According to the passage, why is winning Olympic medals so encouraging?

A．It inspires people’s deep love for the country.

B．It proves the exceptional skills of the winners.

C．It helps the country out of natural disasters.

D．It earns the winners fame and fortune.

【小題4】Iribarne’s goal of forming the foundation is to ________.

A．bring fun to poor kids

B．provide soccer balls for children

C．give poor kids a chance for a better life

D．a(chǎn)ppeal to soccer players to help poor kids

What makes one person more intelligent than another? What makes one person a genius, like the brilliant Albert Einstein, and another person a fool? Are people born intelligent or stupid, or is intelligence the result of where and how you live? These are very old questions and the answers to them are still not clear.
We know, however, that just being born with a good mind is not enough. In some ways, the mind is like a leg or an arm muscle. It needs exercise. Mental (done with the mind) exercise is particularly important for young children. Many child psychologists (心理學家) think that parents should play with their children more often and give them problems to think about. The children are then more likely to grow up bright and intelligent. If, on the other hand, children are left alone a great deal with nothing to do, they are more likely to become dull and unintelligent.
Parents should also be careful with what they say to young children. According to some psychologists, if parents are always telling a child that he or she is a fool or an idiot, then the child is more likely to keep doing silly and foolish things. So it is probably better for parents to say very positive (helpful) things to their children, such as “That was a very clever thing you did.” or “You are such a smart child.”
【小題1】The words “intelligent” and “brilliant” in the first paragraph probably mean _______ while “dull” in the second paragraph means ________.

A．bright and splendid; slow in thinking and understanding

B．pretty and handsome; ordinary-looking

C．great and important; common

D．hopeful and helpful; careless

【小題2】According to the context we can guess that a genius is ________ while an idiot is ________.

A．a(chǎn) normal person; a funny person

B．a(chǎn) strong person; a weak person

C．a(chǎn) highly intelligent person; a foolish or weak-minded person

D．a(chǎn) famous person; an ordinary person

【小題3】A person ________ is more likely to become a genius.

A．whose parents are clever

B．often thinking about difficult problems

C．often helped by his parents and teachers

D．born with a good brain and putting it into active use

What would life be like without rich, creamy, mouthwatering, melt-in-your-mouth chocolate?
Life would be bitter for most Americans. They spend about $13 billion a year buying all sorts of chocolate treats.
However, for the African children who toil under slavelike conditions on cacao plantations, life is not sweet. The cacao bean is the main ingredient in the chocolate. According to a 2002 survey by the International Institute of Tropical Agriculture and the US Agency for International Development, about 284,000 children work in dangerous conditions on cacao farms in western Africa.
More than half those children are younger than 14. Many were sold into forced labor to work 12 hours or more a day on the cacao plantations.
A number of international organizations, including several African governments, recently began a program to eliminate(消除) child labor on cacao plantations. Under the program, government officials will remove children from abusive working situations while teaching farmers about child labor issues.
The program will also make borrowing money easier for cacao farmers. Officials hope farmers will use the money to invest in their farms and hire paid laborers.
【小題1】The cacao bean is the main ingredient in _______.

A．treats

B．coffee

C．chocolate

D．cigarettes

【小題2】How many children under 14 work on cacao farms in western Africa?

A．About 284,000.

B．About 142,000.

C．About 467,000.

D．About 876,000.

【小題3】From the passage, you can reasonably conclude that _______.

A．cacao farms in western Africa rely heavily on child labor

B．children in Africa know how to make the best chocolate

C．candy bars sold in the United States are made on plantations in Africa

D．eating too much chocolate is bad for your health

Imagine that the genome （基因組） is a book．The book consists of 23 chapters with thousands of stories made up of paragraphs, words and letters on different levels．There are one billion words in the book, as long as 800 Bibles; if I read the genome out to you at the rate of one word per second for eight hours a day, it would take me centuries; if I wrote out the human genome, one letter per millimeter, my text would be as long as the River Danube．This is a huge volume, a book of great length, but it all fits inside an extremely small cell nuclear（細胞核） that fits easily upon the head of a pin．
The idea of the genome as a book is not, strictly speaking, even a metaphor．It is true to a great extent．A book is a piece of digital information, written in one-directional form and defined by a code that translates a small alphabet of signs into a large dictionary of meanings through the order of their groupings．So is a genome．The only difference is that all English books read from left to right, while some parts of the genome read from left to right while some from right to left, but never both at the same time．
While English books are written in words of different lengthens using twenty-six letters, genomes are written entirely in words of three-letter length, using only four letters, and instead of being written on flat pages, they are written on long chains of DNA molecules （分子）．
The genome is a very clever book, because in the right condition it can both photocopy itself and read itself．
【小題1】How do human genomes read according to the passage?___________

A．Only from left to right．

B．Only from right to left．

C．From both directions at the same time．

D．From one direction at a time．

【小題2】We can learn from the passage that the human genome ________．

A．is as long as the River Danube

B．can be easily placed on the head of a pin

C．is coded with an alphabet of four letters

D．is smart enough to read and take photos of itself

【小題3】It can be concluded that the passage is mainly written for ______．

A．specialists in the field

B．general readers

C．natural scientists

D．readers with professional knowledge

【小題4】The real purpose of the author’s comparison of the genome to a book is _____．

A．to focus on the differences between the two

B．to lay emphasis on the similarities between the two

C．to simplify the concept of the human genome

D．to give an exact description of the human genome

BEIJING--Alarmed by the overreaching ambitions of many Chinese provinces to grow at all costs, China’s top economic chief is calling on officials to calm down and spare a thought for the environment．
Zhang Ping, who heads China’s National Development and Reform Commission, the central economic planning agency, said only five or six of China’s 30 provinces are targeting annual economic growth of 8 percent or 9 percent．
The remaining provinces are aiming for growth rates of more than 10 percent this year, with some wanting to double economic output in the coming five years．
“China has a planned energy supply of about 4 billion cubic tons of coal equivalent（等量的）for the next five years, and this is not enough to meet demands for economic growth to double,” he was quoted as saying on the news portal Sina．Com．
Beijing is increasingly concerned with the ambitions of Chinese provinces across the country to chase high growth despite the central government’s urgent request for a more moderate and sustainable（可持續(xù)的）pace of expansion．
Years of rapid economic growth has taken a toll on China’s environment, with Beijing trying to remove some of the damage now．It has an annual growth target of 7 percent for the next five years, well down from last year’s 10 percent．
Zhang said Beijing has asked local governments to take into account the supply of “energy, environment, water and land” to set more reasonable growth targets．
【小題1】Which of the following statements is TRUE according to the passage?

A．Many Chinese provinces are alarmed by Beijing．

B．Zhang Ping is an expert and economic chief from www. Sina.Com．

C．The supply of the coal in China is not sufficient(足夠的) for the next five years．

D．Few Chinese provinces are aiming for economic growth rates of less than 10%．

【小題2】The underlined phrase “taken a toll on” in the sixth paragraph means “_________”．

A．looked forward to	B．paid attention to
C．caused damage to	D．a(chǎn)ttached importance to

【小題3】The general idea of the whole passage can be that ________．

A．China’s economy is developing

B．China’s top chief places more emphasis on the environment

C．a(chǎn)ll Chinese provinces should slow down their economic growth rates

D．economic high growth should go hand in hand with environmental protection

【小題4】What could be the best title for the news?

A．Economic Development	B．Energy Supply
C．Sustainable Development	D．Environment protection