题目内容


An Experiment
Materials: Newspaper, ‘ACE’ hardware ruler (1/8 “think”), a flat table.
Purposes: We’ll show that there is air pressure pushing on us, from every direction while we’re on this Earth.


 
Procedure:

First put a thin ruler on a flat table with a little
less than half of it hanging off the edge of the table
(see the drawing below). Next place a sheet of newspaper
over the ruler flat against the table. Make sure to have
as little air as possible under the paper so that the fold line of the newspaper is at the ruler. Then quickly strike the end of the ruler hanging off the edge of the table. If you strike it quick enough, the ruler will break near the table edge.
What’s going on?
The Earth is covered in a layer of air that is nearly 80 miles thick and at sea level (the bottom) exerts or ‘pushes’ hard almost 15 pounds of pressure per square inch. That means that a full sheet of newspaper laid out flat has nearly 9,300 pounds of air above it.
When you break the ruler above, you are able to break it because of the 'heavy' air pushing down on the paper while you quickly strike the ruler. At first the table is pushing back on the paper, and if you move the ruler quick enough, other air around the edges of the paper can't get under the paper fast enough, so you are trying to lift that 9,300 pounds with the ruler! Some air gets under the paper, but not enough, so the ruler breaks.
1.By doing the experiment, we may realize         .
A.that air exits everywhere
B.why there are directions
C.that we live with air pressure
D.how air helps on the earth
2.How many steps are there in this experiment?          .
A.2      B.3       C.4       D.5
3.The underlined word “exert” probably means       .
A.cover completely            B.advocate actively    
C.influence gradually  D.press heavily
4.The ruler breaks under a quick strike mainly because of          .
A.the air pressure on the newspaper   B.the heavy weight of the newspaper
C.the heavy weight of the flat table    D.the strong power used on the ruler

小题1:C
小题2:B
小题3:D
小题4:A
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In the modern society there is a great deal of argument about competition. Some value it highly, believing that it is responsible for social progress and prosperity (繁荣). Others say that competition is bad, that it sets one person against another, that it leads to unfriendly relationship between people.
I have taught many children who held the belief that their self-worth relied on how well they performed at tennis and other skills. For them, playing well and winning are often life-and-death affairs. In their single-minded pursuit (追求) of success, the development of many other human qualities is really forgotten.
However, others take an opposite attitude. In a culture which values only the winner and pays no attention to the ordinary players, they strongly blame competition. Among the most vocal are youngsters who have suffered under competitive pressures from their parents or society. Teaching these young people, I often notice that they have a desire to fail. They seem to choose failure by not trying to win or achieve success. By not trying, they always have an excuse: “I may have lost, but it doesn’t matter because I really didn’t try.” They don’t believe that if they had really tried and lost, such a loss would prove their worth. Clearly, this belief is the same as that of the true competitors who try to prove themselves. Both are based on the mistaken belief that one’s self-respect relies on how well one performs in comparison(比较) with others. Both are afraid of not being valued. Only as this basic and often troublesome fear begins to dissolve (缓解) can we discover a new meaning in competition.
小题1:What does this passage mainly talk about?
A.Competition helps set up self-respect.
B.Failures are necessary experiences in competition.
C.Competition is harmful to personal quality development.
D.Opinions about competition are different among people.
小题2:Why do some people value competition according to the passage?
A.It builds up a sense of duty.B.It pushes society forward.
C.It improves personal abilities.D.It encourages individual effects.
小题3:The underlined phrase “the most vocal” in Paragraph 3 refers to_______.
A.those who try their best to win
B.those who value competition most highly
C.those who are against competition most strongly
D.those who rely on others most for success
小题4:What is the similar belief of the true competitors and those with a “desire to fail”?
A.One’s success is based on how hard he has tried.
B.One’s success in competition needs great efforts.
C.One’s achievement is determined by his particular skills.
D.One’s worth lies in his performance compared with others’.
小题5:Which point of view may the author agree to?
A.Every effort should be paid back.
B.Competition should be encouraged.
C.Winning should be a life-and-death matter.
D.Fear of failure should be removed in competition.

You often hear people refer to Africa as a country, not a continent. It is often a region that is described as being unified around poverty, disease and despair. Africa is far from being a homogenized continent. It has more than 50 countries, each with unique culture, landscape and tradition.
Africa’s diversity is apparent to anyone who travels to the continent. In the north, you have countries like Morocco, Algeria and Egypt, which have a long tradition of welcoming visitors. Further south there is Kenya and Tanzania, both renowned for their wildlife and for Africa’s tallest peak, Mt. Kilimanjaro. On the southern tip of the continent is South Africa, the region’s economic and political superpower which in itself lies many fascinating cultures. There are also the trouble spots like Congo and Sudan which are almost all but avoided by travelers.
Travel in Africa can be rough. It can also be a great joy. If you have patience, a willingness to maintain an open mind, a desire to explore and the ability to laugh at the strange, your African travels will change your life.
There are many entry points to Africa. Your best bet in terms of cheap airfare is to fly into one of the bigger cities like Johannesburg or Nairobi. Depending on where you are starting from flights to Africa can be either quite cheap or outrageously expensive. As is true nearly everywhere, flying into the biggest cities is usually your best bet for a cheap ticket.
Many people who travel to Africa prefer to do so in a group or through an organized adventure trip. This is especially the case with safari trips. BootsnAll has some of the best African adventure trips and safaris in the world. We work closely with local tour providers to offer you many options at very affordable rates.
If you are looking for a place to stay in, check out the hotels in Africa or the hostels in Africa for those on a tighter budget.
Still want more? You can learn from those who have been to Africa by sharingideas and thoughts on our Africa community message board.
1.From the first paragraph, we know when mentioning Africa, people often_______.
A.regard it as a continent, nota country    
B.connect it with poverty, disease and despair
C.consider it a nice place to travel in
D.admit there are more than 50 countries.
2.Africa’s tallest peak, Mt. Kilimanjaro is________.
A.in the north      B.in the south      C.in the middle    D.off the sea shore
3.What can we infer from the underlined part in Para.2?
A.Travelers seldom go to visit Congo or Sudan.
B.People in Congo and Sudan are trouble-makers.
C.Congo and Sudan are as powerful as South Africa.
D.There are few sightseeing spots in Congo or Sudan.
4.Your African travels will be a great joy, if you have_________.
①patience     ②a willingness to maintain an open mind
③a desire to explore     ④the ability to laugh at the strange
A.①②③     B.①③④     C.②③④     D.①②③④
5.What’s the author’s purpose in writing this passage?
A.Introducing some information of Africa.      
B.Encouraging people to travel in Africa.
C.Reminding travelers of the danger in Africa.
D.Telling people the cheap air fare to Africa.

Obesity(肥胖) in children and adolescents is rising at an alarming rate. Currently over 15% of young people over 6 years old are obese, and obesity is also increasing among children aged 5 and younger.
Children are considered to be overweight if the BMI(Body Mass Index) is over 85% of the weight group in their age and sex categories. If it is 95% and over, they are considered to be obese. Adolescents are generally judged according to adult criteria(标准) for obesity, although there are other considerations in this population, for many factors will affect the result of these measurements.
Causes and Risk Factors for Obesity in Children
Lifestyle Factors. Without educational or parental guidance, children are extremely greatly exposed to the cultural pressures that are largely responsible for growth of the obesity. Neither the media nor the educational system has strong programs that encourage healthy way of life, including exercise and healthy foods. The following are some specific problems created by the culture:
﹡Too much television watching plays an important role in obesity in children. Not only is it a passive activity, but television also offers countless temptations(诱惑) with its advertisements for fast foods, sugar cereals, and unhealthy snacks. In one study obesity rate were lowest in children who watched television one hour or less a day and highest in those who watched four or more hours.
﹡Sugar, particularly from soda, other sweet drinks, and fruit juice, may be major contributors to childhood obesity. One study reported that drinking soda regularly increases a child’s risk for obesity by 60%.
﹡Less physical exercise and greater sitting activities play another significant role in obesity in children. A high level of physical activity – not just using up energy – is important for weight control in young people.
Family History. Parental obesity more than doubles the risk that a young child, whether thin or overweight, will become obese as an adult. In older children and teenagers, obesity in parents starts to affect less as a predictor(预言) for body weight than their own weight. The risk may be due to environmental or genetic factors, or both.
Ethnic and Socioeconomic Factors. As in adult populations, children from lower socioeconomic groups and minority populations are at higher risk for obesity. For example, among young Mexican Americans and African Americans, there has been an increase in overweight trend of about 13% to over 23%.
69.What’s the main idea of the passage? ______________.
A. The trend of obesity                B. Causes of obesity
C. Fight against obesity                D. Obesity in children
70.How many main factors leading to obesity in children are mentioned?
A. 2              B. 3                C. 4                 D. 5
71.According to the passage, which of the following children is most likely to be obese?
A. A 5-year-old child whose parents are overweight.
B. A 16-year-old teenager whose parents are obese.
C. A child who watches TV one hour per day.
D. A child who take regular exercise.
72.Which of the following is NOT true?
A. Parents should give some guidance on healthy lifestyles.
B. Watching TV four hours a day will surely lead to obesity in children.
C. Children from minority populations are more likely to be obese.
D. Children should take more physical exercises.

第二部分:语言知识及运用(共两节,满分35分)
第一节:完形填空(共10小题;每小题2分, 满分20分)      
阅读下面短文,从各题所给的四个选项A、B、C、D中选出最佳选项。
The guitar is one of the oldest instruments known to man. It   21   originated in the vicinity of (在……附近) China. There were guitars in ancient Egypt and Greece as well, but the   22   history of the guitar started in Spain in the 13th century. By 1500 the guitar was   23   in Italy, France, and Spain. A French document of that time   24   that many people were playing the guitar. Stradivarius, the famous king of violin makers, could not resist   25   a variety of guitars. Also, there was no lack of music written for the instrument. Haydn, Schubert, and others   26   guitar music. When Beethoven was asked to compose music for the guitar, he went into a rage(大怒) and   27  , but eventually even Beethoven could not ignore the   28  .Legend tells us he finally called the guitar a miniature orchestra. Indeed the guitar does   29   like a little orchestra! Perhaps that is why in rural areas around the world the guitar has been a source of   30   for millions to enjoy.
21. A. certainly             B. mainly                     C. probably           D. partly
22. A. written                      B. learned              C. found                D. spoken
23. A. acceptable           B. popular            C. familiar             D. available
24. A. predicted            B. warned              C. denied               D. recorded
25. A. destroying           B. accusing            C. creating             D. following
26. A. enjoyed                     B. wrote                C. accepted            D. commented
27. A. refused               B. accepted            C. failed                D. escaped
28. A. contribution        B. challenge           C. history                     D. suggestion
29. A. look                   B. feel                   C. taste                  D. sound
30. A. intelligence         B. energy                     C. music                D. spirit
Each year, road accidents kill a million people and injure millions more . The economic costs are greatest for developing countries . Earlier this year , the United Nations called for a campaign to improve road safety .
One way to avoid accidents is better driving . Another is better roads and bridges . Engineers in the Unites States have designed ten new concrete mixtures that they think could make bridges last longer .
Professor Paul Tikalsky leads the experiments by a team at Pennsylvania State University . He says bridges made of concrete now last about twenty-five to thirty-five years . But he says the new mixtures might extend that to seventy –five or even one-hundred years .
Concrete is made of stone , sand , water and cement(水泥). The materials in the cement hold the concrete together . Ancient Romans built with concrete . Yet strengthened concrete bridges did not appear until the late 1800s . People keep looking for new ways to improve concrete . Professor Tikalsky says it is one of the most complex of all chemical systems .
The new mixtures designed by his team contain industrial waste products . He says these make the concrete better able to resist damage from water and salt over time . One of the products is fly ash . This is released into the air as pollution when coal is burned .
Professor Tikalsky says particles (颗粒)of fly ash are almost exactly the same size and chemical structure as Portland cement . This is the most costly material in concrete . So using fly ash to replace some of it would save money .
The federal government is paying for part of the research . Engineers anywhere can use the technology . Professor Tikalsky says some of the ideas have already been put to use in China , the Philippines and other countries .
小题1:Why did the United Nations launch the campaign ?
A.Because the United Nations wanted to reduce road accidents and economic costs
B.Because two million people were killed in the accidents .
C.Because engineers wanted to design ten new concrete mixtures .
D.Because the United Nations made bridges of the new mixtures which could last for about 20 to 35
years .
小题2:What does the underlined word “ this ” in the sixth paragraph refer to ?
A.Fly ashB.Portland cementC.SandD.Chemical
小题3:Which of the following statements is TRUE ?
A.Ten new concrete bridges have already been built in the United States .
B.A new concrete bridge could last 50 more years than an ordinary concrete one .
C.People didn’t know how to build with cement until the late 1800s .
D.Water and salt won’t do any damage to bridges over time .
小题4:What does the passage mainly tell us ?
A.The causes of road accidents .B.The advantages of fly ash
C.The measures of avoiding road accidentsD.Latest information about long-life concrete bridges

(二)
A
How Do Animals Catch Their ZZZ’s?
Different creatures have developed some pretty creative ways to get their rest and stay safe. The lizard(蜥蝎)likes to sleep at the far end of small branches hanging out over a pond or lake in the rain forest. If a snake tries to slither up the branch to eat it ,it will shake the branch and knock the lizard off ,and the lizard will fall safely into the water. Chameleons can change color to match their surroundings in order to hide even while sleeping.
Corillas(大猩猩)like to sleep high in the trees. They build a new bed every night, sometimes taking up to half an hour to pile branches ,twigs ,and leaves into a comfortable bed .Birds also find it safe to sleep in the trees, but unless they have eggs or young chicks ,they don’t use a nest .They just lock their feet around a branch and hang on .A special tendon(腱)in their legs in automatically tight when they are at rest ,so they won’t let go and fall.
Dolphins live underwater ,but must come to the surface to breather .Scientists now believe that dolphins may sleep with only half their brain, while the other half stays awake to keep them safe and breathing. Seals also do this ,lying on their sides on the surface of the water with one flipper underwater paddling to keep their noses above the surface. Some ducks may also have this ability, and actually sleep with one eye closed and one eye open.                          
56.How many animals are mentioned in this passage?
A.6.                       B.7.                       C.8.                       D.9.
57.How does a chameleon protect itself while sleeping?
A.By changing its body colors.                 B.By hinging out over a pond.
C.By sleeping with half their brain.          D.By making beds with branches.
58.Why will not birds fall when they are at rest?
A.They build nests and sleep in them.       B.They fall asleep automatically.
C.They have a loose tendon in their legs.   D.They lock their feet around a branch.
59.What does the writer intend to tell us?
A.The cleverest animal is the gorilla because it can make beds.
B.Differences in habitat could lead to different living habits.
C.The ways animals catch their ZZZ’s are pretty much he same .
D.In order to protect themselves most animals choose not to sleep.

(十)
The first breath-taking pictures of the Earth taken from space showed it as a solid ball covered by brown land masses and blue-green oceans. We had never seen the Earth from that distance before. To us, it appeared as though the Earth had always looked that way and always would. Scientists now know, however, that the surface of the Earth is not as permanent as we had thought.
Scientists explain that the surface of our planet is always moving. Continents moves about the Earth like huge ships at sea. They float on pieces of the Earth’s outer skin. New outer skin is created as melted rock pushed up from below the ocean floor. Old outer skin is destroyed as it rolls down into the hot area and melts again.
Only since the 1960s have scientists really began to understand that the planet Earth is a great living machine. Some experts have said this new understanding is one of the most important revolutions in scientific thought. The revolution is based on the work of scientists who study the movement of the continents—a science called plate tectonics.
The modern story of plate tectonics begins with the German scientist Alfred Wegener. Before World War One, Wegener argued that the continents had moved and were still moving. He said the idea first occurred to him when he observed that the coastlines of South America and Africa could fit together like two pieces of a puzzle. He proposed that the two continents might have been one and then split apart.
Wegener was not the first person to wonder about the shape of the continents. About 500 years ago, explorers thought about it when they made the first maps of Americas. The explorers noted the east coast of North America and South America would fit almost exactly into the west coast of Europe and South Africa. What the explorers did not do, but Wegener did, was to investigate the idea that the continents move.
1. What does the writer mainly tell us in the passage?
A. The first breath-taking pictures of the Earth taken from space.
B. Human’s recognition of the earth’s surface.
C. The German scientist Alfred Wegener.
D. The early explorers’ discovery.
2. Which of the following is true according to the passage?
A. We didn’t see the Earth from far away until we saw the picture taken in the space.
B. Our ancient thought that the surface of the earth is still.
C. Alfred Wegener was not the first person to investigate the idea that the continents move.
D. The coastline of India and Africa fit together.
3. The last word of the third paragraph “tectonics” mean “________”.
A. study of construction
B. study of architecture
C. earth surface
D. structural geology
4. What did the explorers find?
A. The coastlines of South America and Africa could fit together.
B. The coastlines of North America and Africa could fit together.
C. The east coastlines of North America and the west coast of Europe could fit together.
D.The coastlines of North America and India could fit together.

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