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科目: 来源: 题型:阅读理解

15.Two-thirds of the world's major rivers have now been disrupted(中断)with more than 50,000 dams in an attempt to stole water and provide power.In the US,there are more than 85,000 dams,disrupting large and small rives,and in most cases transforming natural flow.The most famous of these,the Hoover Dam,constructed in the l930's,is mainly responsible for the fact that the Colorado River no longer reaches the ocean.
    Dams,besides all their attractive benefits,also have negative impacts.Creating a reservoir means a large area must be flooded.Communities may lose their land,houses and culturally impotent sites.
    Environmentally,the new reservoir can be a paradise for wildlife,especially birds.However,it can cause greenhouse gas emissions(排放)and poison the water for fish.Also,the dramatic rise and fall of water levels during dam releases is too extreme for plains and animals to cope with,resulting in dead zones around the shores of reservoirs.Fish that lay their eggs in the shallows,for example,may find a few hours later that those sites are high and dry.
    Dams don't just block water flow.They also prevent fish migrations,and are a barrier to sediment (沉淀物)flows.Instead of rushing downriver,sediments get backed up against the dam wall,which cause the reservoir level to increase over time.However,sediments which are rich in nutrients have become a problem.The fertility of the entire system can be influenced,with soils lost during seasonal rains not being replaced.
     Perhaps the biggest problem can be seen in deltas(三角洲),often host to large cities,which are sinking into the oceans.Groundwater is being extracted to feed the city,causing the urban weight to sink and sediments washed away by the ocean are no longer being replaced.The result is that sea level rise in cities from Shanghai to Alexandria.
51.What effects does creating a reservoir have on people's life?D
  a.People will see fewer birds near the rivers.
  b.Farmers below the dam may have less water to irrigate their fields
  c.Visitors can't see some cultural relics anymore.
  d.More conflicts and wars over water will break out
  e.More kinds of fish will become extinct in the future
  A.a,c    B.c,e    C.b,e   D.b,c
52.With many dams built across rivers,fish willB
  A.find more places to lay their eggs    B.face a more dangerous living habitat
  C.feed on more sediment rich in nutrients D.find it easier to deal with the rise of water
53.How can dams influence the cities like Shanghai?C
  A.Its entire system will be influenced.    B.The rainy season will last longer.
  C.It will lie below sea level in the future   D.Rich soils will be washed away
54.What does the text mainly talk about?A
  A.Environmental loss of dams.B.Cultural loss of dams
  C.Economical gain of dams      D.Environmental benefits of dams
55.Where can we most probably read this passage?C
    A.In a travel magazine     B.In a personal diary
    C.In a science report       D.In a biology textbook.

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科目: 来源: 题型:选择题

14.When he was in high school,he made up his mind to     membership in the Party.(  )
A.1earn fromB.apply forC.take inD.join in

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科目: 来源: 题型:阅读理解

13.When Siva Kalyan was born,his backbone was deformed(畸形的)resulting in a lifelong difficulty in walking.But that hasn't stopped the nine-year-old from becoming a prodigy(天才).
Until he was three-and-a-half years old,Siva could not even crawl.Wanting the best treatment for their son,Siva's parents moved with him from India to Australia and later to the USA.
In the USA,his parents enrolled(使入学)him in the second grade based on his age.But his teachers soon realized they had a genius.Siva was then tested for the eighth grade,but it was soon found out that he was actually qualified for college courses.As one advanced course was not enough,the brilliant boy is now taking two courses from Stanford University.Due to the treatment he received,Siva's physical condition has improved as well.
But none of this"just happened".It was his parents'understanding and correct guidance,and the loving care of his grandparents that contributed to the growth of the genius.Siva's highly educated and hardworking family has brought him up on the basis of certain principles.
The family believes that once a strong foundation is built for the child in English and mathematics,the child is equipped to master any other subject,law,history,or engineering.It is equally important to recognize the strengths of a child rather than forcing the child to do things that he may not want to do.
Siva's parents helped.Siva focus his energies on his strength,which is mathematics.At the same time they took care to see that he had friends to play with and enjoyed a few recreational activities.The only activity that's restricted for Siva is viewing television.Siva watches TV only for 30 minutes a day and video games are a bonus for special occasions.
Thanks to his mother who is a singer,Siva has also learned music and even won the first and second prize at two competitions.In sports,he likes to swim.He began to learn swimming to strengthen his muscles,and by the age of eight he was able to swim a kilometer in both the backstroke and the freestyle.

56.Why did Siva's parents move to the USA?B
A.They wanted to give their son the best education.
B.They wanted their son to receive the best treatment.
C.They weren't used to life in India or Australia.
D.They wanted their son to go to Stanford University.
57.The underlined word "this" in the fourth paragraph refers to the fact thatD.
A.Siva's parents enrolled him in the second grade
B.Siva's physical condition improved
C.Siva was tested for the eighth grade
D.Siva became a genius despite his disability
58.The family believes thatB.
A.English and mathematics are easier to learn than other subjects
B.it is important to recognize the strengths of a child
C.a child must learn English rather than law or history
D.forcing a child to do things is also quite important
59.What can we learn about Siva?A
A.He is really good at mathematics.
B.He has no friends to play with.
C.He is not allowed to play video games.
D.He learned swimming from his mother.
60.The text is mainly aboutA.
A.the growth of a disabled child prodigy   
B.certain principles to bring up a child
C.the special ways to train a genius       
D.the influence of parents on their child.

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科目: 来源: 题型:阅读理解

12.Scientists have discovered thirteen kinds of vitamins.They say vitamins help to carry out chemical changes within cells.If we do not get enough of the vitamins we need in our food,we are at risk of developing a number of diseases.Which foods should be eaten to keep us healthy?Let us look at some important vitamins.
Vitamin A helps prevent skin and other tissues from becoming dry.People who do not get enough vitamin A cannot see well in darkness.Vitamin A is found in fish liver oil and the yellow part of eggs.
Vitamin B-1is also called thiamine.Thiamine changes starchy(含淀粉的)foods into energy.Thiamine is found not just in whole grains like brown rice,but also in beans and peas,nuts,and meat and fish.
Vitamin B-12is needed so folic acid can do its work.Together,they help produce red blood cells.Folic acid has been shown to prevent physical problems in babies when taken by their mothers during pregnancy.Vitamin B-12is found naturally in foods like eggs,meat,fish and milk products.Vitamin B-12is found in green leafy vegetables and other foods,like legumes and citrus fruits (柑橘类水果).
Vitamin C is needed for strong bones and teeth.The body stores little vitamin C.So we must get it every day in foods such as citrus fruits,tomatoes and uncooked cabbage.
Vitamin D prevents the children's bone disease rickets (佝偻病).Ultraviolet light from the sun changes a substance in the skin into vitamin D.Fish liver oil also contains vitamin D.
Vitamin K is needed for healthy blood.It thickens the blood around a cut to stop bleeding.It can also be found in pork products,liver and in vegetables like cabbage,kale and spinach (菠菜).
Vitamins are important to our health.A lack of required vitamins can lead to health problems.

28.What is the main idea of the passage?D
A.There are thirteen kinds of vitamins in total.
B.One can not live without enough vitamins.
C.Vitamins can carry out chemical changes within cells.
D.Enough vitamins are vital to keep healthy.
29.Women who wish to become mothers should take inC.
A.vitamin A      
B.vitamin B-1      
C.vitamin B-12      
D.vitamin C
30.What can change a substance in the skin into vitamin D?B
A.Fish liver oil.
B.Ultraviolet light from the sun.
C.Fresh milk drunk by people.
D.Doing a certain amount of exercise.
31.According to the passage,taking in enough vitamin C canC.
A.make our eyesight better             
B.help to stop bleeding
C.make our bones and teeth strong       
D.help produce red blood cells.

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科目: 来源: 题型:阅读理解

11.The economic growth that many nations in Asia and increasingly Africa have experienced over the past couple of decades has transformed hundreds of millions of lives-almost entirely for the better.But there's a byproduct to that growth,one that's evident-or sometimes less than evident-in the smoggy,smelly skies above cities like Beijing,New Delhi and Jakarta.Thanks to new cars and power plants,air pollution is bad and getting worse in much of the world,and it's taking a major toll (伤亡人数,代价) on global health.
How big?According to a new analysis published in the Lancet,more than 3.2 million people suffered deaths from air pollution in 2010,the largest number on record.That's up from 800,000 in 2000.And it's a regional problem:65% of those deaths occurred in Asia,where the air is choked by diesel soot (内燃发动机烟雾) from cars and trucks,as well as the song from power plants and the dust from endless urban construction.In East Asia and China,1.2 million people died,as well as another 712,000 in South Asia,including India.For the first time ever,air pollution is on the world's top-10 list of killers,and it's moving up the ranks faster than any other factor.
So how can air pollution be so damaging?It is the very finest soot-so small that it roots deep within the lungs and from the enters the bloodstream-that contributes to most of the public-health toll of air pollution including death.Diesel soot,which can also cause cancer,is a major problem because it is concentrated in cities along transportation zones affecting overpopulated areas.It is thought to contribute to half the deaths from air pollution in urban centers.Fro example,1 in 6 people in the U.S.live near a diesel-pollution hot spot like a rail yard,port terminal or freeway.
We also know that air pollution may be linked to other non-deadly diseases.Fortunately in the U.S.and other developed nations,urban air is for the most part cleaner than it was 30 or 40 years ago,thanks to regulations and new technologies like the catalytic converters (催化式排气净化器) that reduce automobile emissions.Govemments are also pushing to make air cleaner-see the White House's move last week to further tighten soot standards.It's not perfect,but we've had much more success dealing with air pollution than climate change.
Will developing nations like India eventually catch up?Hopefully-though the problem may get worse before it gets better.The good news is that it doesn't take a major technological advance to improve urban air.Switching from diesel fuel to unleaded (无铅燃油) helps,as do newer and cleaner cars which are less likely to send out pollutants.Power plants-even ones that burn mineral fuels like coal-can be fitted with pollution-control equipment that,at a price,will greatly reduce smog and other pollutants.
But the best solutions may involve urban design.In the Guardian,John Vidal notes that Delhi now has 200 cars per 1,000 people,far more than much richer Asian cities like Hong Kong and Singapore.Developing cities will almost certainly see an increase in care ownership as residents become wealthier-and that doesn't have to mean deadly air pollution.Higher incomes should also lead to tougher environmental regulations,witch is exactly what happened in the West.We can only hope it happens before the death toll from bad air gets even higher.
41.What tends to give rise to the highest death toll according to the passage?D
A.The lack of tight environmental protection standards.
B.The increasing numbers of the diesel cars and trucks.
C.The frighteningly high death rate from deadly cancer.
D.The world's serious air pollution such as soot and dust.
42.The"byproduct"(Paragraph 1)most probably refers toA
A.consequence      B.solution         C.reform           D.design
43.The basic reason why so many people die from air pollution is thatC
A.the diesel soot is too small to be seen
B.the diesel soot is much too poisonous to breathe
C.the diesel soot roots in lungs and gets into blood
D.the diesel soot can also contribute to deadly cancer
44.According to the passage,the writer actually wants to convince the readers thatD   
A.the global economic growth is mainly to blame for air pollution and climate change
B.the developing countries are repeating the same mistakes as the developed ones made
C.the ecological situation and air pollution in India are becoming worse and worse
D.the unbeatable air is increasingly becoming a major killer throughout the world 
45.By describing urban design as"the best solution"in the last paragraph,the writer means thatB
A.the making of tougher environmental regulations alone is of little use
B.more sever regulations should be made to handle air pollution
C.the urban construction in western developed countries is the best choice
D.the pace of development has to be slowed down to reduce air pollution.

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科目: 来源: 题型:阅读理解

10.Australian cities can keep their native wildlife-but only if they can kick their habit of urban sprawl (无计划的扩展).That's the finding of a new study by leading Australian environmental researchers Jessica Sushinsky,Professor Hugh Possingham and Dr Richard Fuller of The University of Queensland.
"While urban development usually reduces the number of birds in a city,building more compact (紧凑的) cities and avoiding urban sprawl can slow these reductions greatly,"says lead author Jessica Sushinsky."Compact housing development leaves birds'homes untouched,leading to fewer losses of birds."
The researchers surveyed native and wild birds in Brisbane's urban areas,including living and industrial areas,public parks and gardens,major roadways and airports.They then used statistical modeling to find out what will happen to the birds as the city grows.The first setting was compact growth-where multiple homes are built on land that previously had only one house.The second setting was sprawling growth-a familiar pattern where homes are built here and there beyond the city's current boundaries.
The team's forecasts showed that a much greater diversity of species was lost over 20 years in the sprawling setting compared to the more compact setting."Urban sprawl resulted in the disappearance of many urban-sensitive birds-birds that only live in areas where there is native vegetation (植被),such as parklands and woodlands,"Ms Sushinsky says.
"On the other hand,we found the city with the compact development attracted more birds because it kept more of its parks and green areas."
Now the Queensland Government has adopted the more compact urban growth strategy,which,Dr Richard Fuller says,is good news for Australia's native birds.These birds are environmental specialists-they need a particular environment to do well."While compact development means smaller backyards,it can also make our entire cities more biodiverse,"according to Dr Fuller."The study shows that we should hold on to our green spaces instead of clearing them for sprawling development."
This is the first time science has modeled the effects of different urban growth strategies on birds,the researchers say."Statistical models like these are important because they help us to understand the ecological consequences of a particular decision,"says Dr Fuller.
71.The study deals with the relationship betweenA.
A.city development and birds                        B.the environment and birds
C.humans and wildlife                               D.climate and wildlife
72.Why is compact urban growth better than the sprawling strategy?D
A.It makes the cities more beautiful.
B.It gives people larger backyards.
C.It is money-saving.
D.It is bird-friendly.
73.Dr Richard Fuller thinks the Queensland Government's actionB
A.is really brave                                 
B.is worth praising
C.has an uncertain future                        
D.should be performed nationwide
74.What can we learn about the study from the passage?D
A.It is based on the statistics in the past.
B.It is strongly against urban development.
C.It criticizes the city environment in Brisbane.
D.It suggests leaving more green spaces for birds.
75.Where does the passage probably come from?A
A.A news report
B.A travel guide
C.A health magazine
D.A history book.

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科目: 来源: 题型:选择题

9.The use of several senses gives the brain more connections and associations,making it easier ______ information later,which assists memory and learning.(  )
A.findB.findingC.foundD.to find

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科目: 来源: 题型:选择题

8.It is too early to tell whether ________ the public expenses will benefit the company workers or not.(  )
A.cutting downB.cutting upC.cutting offD.cutting away

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科目: 来源: 题型:阅读理解

7.Masses of floating ice are so large that they dwarfs your ship,making you question whether your ship still can be spotted among such floating mountains.They are so improbable looking that you simply look in wonder.It seems that nothing that large could be natural-and then it strikes you that something so large could only be natural.
Now,people realize that as climate change is raising global temperatures,more icebergs are being born.Antarctica creates far more of them than Greenland,the source of bergs in Arctic waters.Antarctica's are also much larger,sometimes reaching the size of small countries.Recent data show the average atmospheric temperature has increased about 4.5°F in the western Antarctic Peninsula since the 1940s,making the region,among the fastest warming on earth.This jump has been shown in the recent breaking of major ice shelves along the Antarctic Peninsula.As a result,thousands of new icebergs have broken off,from ice shelves into the Southern Ocean at an accelerated rate.
Even as more icebergs are being created,scientists are learning that these beauties are far from inactive masses of ice.In fact,they strikingly alter their environments biologically,chemically,and physically,making them islands of life in the open sea.Observers at sea had long remarked that they attract seals,and seabirds,and divers had noticed that fish are more numerous near them than in the surrounding sea.Now scientists are learning just what the attraction is all about.
Depending on their size,location,and the season,icebergs can be nurturers or destroyers.During their existence-typically years from breaking off from an Antarctic or Greenlandic glacier to their gradual melting as they float into lower altitudes,they support animals on,around,even inside their splendid ice castle.They fertilize the ocean with nutrients,increasing sea creature production.Grounded bergs can shelter areas of the seafloor,protecting bottom-living creatures from free-floating icebergs.However,large bergs can also trap sea ice,preventing its annual breakup and thus stopping phytoplankton(浮游植物)from getting life-giving sunlight,breaking the food chain at its first link.…
Icebergs will continue to astonish and attract visitors to the polar regions with their size and extraordinary beauty.But now these frozen masses are taking on a new dimension of wonder as we uncover their vital role in the environment of polar seas.No longer can we look at icebergs as mere passive beauties.They are active  agents of change,each one an icy oasis with a wake of life as it floats on its unstoppable oceanic journey to melting.

67.Why does the author mention "dwarfs your ship" in the first paragraph?D
A.To explain how natural icebergs are.
B.To show how powerful icebergs are.
C.To describe icebergs as floating ships.
D.To tell the unimaginable size of icebergs.
68.What can we learn from the passage?D
A.The temperature in Arctic is rising faster than that in Antarctica.
B.The ocean food chain breaks due to the melting of icebergs.
C.Floating icebergs help shelter bottom-living ocean creatures.
D.Global warming has kept bringing icebergs into being.
69.From the passage we can conclude that icebergs canA.
A.preserve ocean lifeB.carry ocean nutrients away
C.create a warm polar environmentD.keep sea animals away from polar seas
70.What is the author's attitude towards the icebergs?B
A.Cautious.B.Objective.C.Doubtful.D.Disapproving.

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科目: 来源: 题型:阅读理解

6.
For:Doug Smith,Director of wolf recovery,Yellowstone National Park
In the world today there is so much we are losing; more and more species disappear from the earth every year.The time has come to put something back,to restore(恢复)to treat some of the old wounds enforced on nature over the years.
Wolves are animals killing and eating other animals in North America.They play an important role in keeping the continent healthy.Most places don't have enough wild country to make their restoration possible,which means it's even more important to restore wolves where conditions are right,places like Yellowstone,which has both a high level of wildness,as well as abundant creatures that wolves hunt and eat for living.
Some who oppose wolf restoration have a human centered point of view that the earth is here for humans,we can use it whenever we want and for whatever purpose.But wolves offer us a chance to live another way-a way to learn to live with other life forms.
Against:Larry Bourret,Vice President,Wyoming Farm Bureau
What does wolf introduction to Yellowstone mean?To the average citizen it probably just means introducing wolves to Yellowstone.There would be no unfavorable effects because few people live near Yellowstone.
But to farmers it means introducing wolves,which wander over vast areas-in and out of the park-onto their farms.Wolves eat meat-as in the cattle,sheep that keep farmers in business.Introduction apparently also means lawsuits by environmental groups attempting to remove livestock(家畜,牲畜) from federal lands.To farmers,who own private lands in the same area,it means the possibility of ?nancial ruin.To farmers it is a form of land use restrictions.To farmers introducing wolves means taking away the farmers'livelihoods without just compensation.Why do people not want a nuclear power plant built in their backyard?For the same reason farmers do not want wolves introduced into their backyard.
60.What are the two passages mainly about?C
A.How to keep the balance of nature.
B.How to increase the number of wolves.
C.Whether to introduce wolves to Yellowstone.
D.Whether to remove livestock away from federal lands.
61.According to the passage Doug Smith isC.
A.a private land owner
B.an enthusiastic hunter
C.a wildlife conservationist
D.a national park administrator
62.What are the farmers concerned about?B
A.Being forced to leave their homes.
B.Suffering heavy financial loss.
C.Having to sell their farmland.
D.Being controlled by wolves.
63.Why does Larry Bourret mention"nuclear power plant"?B
A.To summarize his opinion.
B.To make his view persuasive.
C.To tell the danger of nuclear power plant.
D.To introduce the background of wolf recovery.

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