科目: 來源: 題型:閱讀理解
Against the supposition that forest fires in Alaska,Canada and Siberia warm the climate,scientists have discovered that cooling may occur in areas where burnt trees allow more snow to mirror more sunlight into space.
This finding suggests that taking steps to prevent northern forest fires to limit the release of greenhouse gases may warm the climate in northern regions.Usually large fires destroyed forests in these areas over the past decade.Scientists predict that with climate warming,fires may occur more frequently over the next several centuries as a result of a longer fire season.Sunlight taken in by the earth tends to cause warming,while heat mirrored back into space tends to cause cooling.
This is the first study to analyze all aspects of how northern fires influence climate.Earlier studies by other scientists had suggested that fires in northern regions sped up climate warming because greenhouse gases from burning trees and plants were released into the atmosphere and thus trapped heat.
Scientists found that right after the fire,large amounts of greenhouse gases entered the atmosphere and caused warming.Ozone (臭氧) levels increased,and ashes from the fire fell on faroff sea ice,darkening the surface and causing more radiation from the sun to be taken in.The following spring,however,the land within the area of the fire was brighter than before the fire,because fewer trees covered the ground.Snow on the ground mirrored more sunlight back into space,leading to cooling.
“We need to find out all possible ways to reduce the growth of greenhouse gases in the atmosphere,” scientists said.They tracked the change in the amount of radiation entering and leaving the climate system as a result of the fire,and found a measurement closely related to the global air temperature.Typically,fire in northern regions occurs in the same area every 80 to 150 years.Scientists,however,found that when fire occurs more frequently,more radiation is lost from the earth and cooling results.Specifically,they determined when fire returns 20 years earlier than predicted,0.5 watts per square meter of area burned are soaked up by the earth from greenhouse gases,but 0.9 watts per square meter will be sent back into space.The net effect is cooling.Watts are used to measure the rate at which energy is gained or lost from the earth.
【小題1】According to the new findings,taking steps to prevent northern forest fires may________.
A.result in a warming climate |
B.cause more forest fires |
C.lead to a longer fire season |
D.protect the forests there |
A.large amounts of greenhouse gases enter the atmosphere |
B.the levels of ozone which is a type of oxygen increase |
C.snow on the ground mirrors more sunlight back into space |
D.a(chǎn)shes from the fire fall on the ice and darken the surface |
A.had analyzed all aspects of how northern fires influenced climate |
B.had indicated that forest fires would pollute the atmosphere |
C.had suggested that people should take measures to protect environment |
D.had suggested that the fires would speed up climate warming |
A.warm the climate as the supposition goes |
B.cool the climate by reflecting more sunlight into atmosphere |
C.make more space for the growth of young trees |
D.help to gain more energy rather than release more energy |
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科目: 來源: 題型:閱讀理解
Global warming is when the earth heats up,the temperature rises.It happens when greenhouse gases—carbon dioxide,water vapor,nitrous oxide(二氧化氮),and methane(沼氣) trap heat and light from the sun in the earth’s atmosphere,which increases the temperature.This is like when heat is trapped in a car.On a very hot day,the car gets hotter when it is out in the parking lot.This is because the heat and light from the sun can get into the car,by going through the windows,but it can’t get back out.Once the light is inside the car,it is trapped and the heat builds up,just like it does in the earth’s atmosphere.This is what the greenhouse effect does to the earth.The heat and light can get through the atmosphere,but it can’t get out.As a result,the temperature rises.
Sometimes the temperature can change in a way that helps us.The greenhouse effect makes the earth appropriate for people to live on.Without it,the earth would be freezing,or on the other hand it would be burning hot.We would not get the sun’s heat and light to make the night somewhat warm.During the day,especially during the summer,it would be burning because the sun would be up with no atmosphere to filter(過濾) it,so people,plants,and animals would be exposed to all the light and heat.
Although the greenhouse effect makes the earth able to have people living on it,if there gets to be too many gases,the earth can get unusually warmer,and many plants,animals,and people will die.They would die because there would be less food (plants like corn,wheat,and other vegetables and fruits).This would happen because the plants would not be able to take in the heat.This would cause us to have less food to eat,but it would also limit the food that animals have.Gradually,people,plants,and animals would all die of hunger.
People are doing many things to try to stop global warming.One thing people are doing is carpooling.Carpooling is driving with someone to a place that you are both going to.This minimizes the amount of greenhouse gases put into the air by a car.
Another thing that people are doing is being more careful about leaving things turned on like the television,computer,and the lights.A lot of people are taking time away from the television,and instead,they are spending more time outdoors.This helps our planet out a lot.Now,more people are even riding buses,walking to school,and riding their bikes to lower the amount of greenhouse gases in the air.
Planting trees and recycling also help.If you recycle,less trash goes to the dump,and less trash gets burned.As a result,there are fewer greenhouse gases in our atmosphere.Although adults do many things to help stop global warming,kids can do just as much.
【小題1】By the example given in Paragraph 1,the author wants to ________.
A.explain how greenhouse gases work |
B.show his feeling in a car in hot summer |
C.tell us cars are causes of greenhouse gases |
D.say that there are greenhouse gases in every car |
A.light | B.heat |
C.temperature | D.greenhouse effect |
A.If there is greenhouse effect,all the plants will die. |
B.Human beings are likely to disappear from the earth. |
C.Crops can’t take the heat if there is greenhouse effect. |
D.Although greenhouse effect is necessary,too much of it causes us to die. |
A.Why cars and buses pollute the air a lot. |
B.What kids can do to help stop global warming. |
C.What global warming is doing to the environment. |
D.Who should be responsible for the environmental problems. |
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科目: 來源: 題型:閱讀理解
LONDON—Here’s a new warning from health experts:Sitting is deadly.
Scientists are increasingly warning that sitting for long periods—even if you also exercise regularly—could be bad for your health.And it doesn’t matter where the sitting takes place—at the office,at school,in the car or before a computer or TV—just the overall number of hours it occurs.Several studies suggest people who spend most of their days sitting are more likely to be fat,have a heart attack or even die.
In an editorial published this week in the British Journal of Sports Medicine,Elin EkblomBak of the Swedish School of Sport and Health Sciences suggested that authorities rethink how they define physical activity to highlight the dangers of sitting.
While health officials have issued guidelines recommending minimum amounts of physical activity,they haven’t suggested people try to limit how much time they spend in a seated position.
“After four hours of sitting,the body starts to send harmful signals,”said EkblomBak.She explained that genes regulating(調(diào)節(jié)) the amount of glucose(葡萄糖) and fat in the body start to shut down.
Even for people who exercise,spending long periods of time sitting at a desk is still harmful.Tim Armstrong,a physical activity expert at the World Health Organization,said people who exercise every day—but still spend a lot of time sitting—might get more benefit if that exercise was spread across the day,rather than in a single bout(一回).
Still,in a study published in 2009 that tracked more than 17,000 Canadians for about a dozen years,researchers found people who sat more had a higher death risk,whether or not they exercised.
“We don’t have enough evidence yet to say how much sitting is bad,” said Peter Katzmarzyk of the Pennington Biomedical Research Center in Baton Rouge,who led the Canadian study.“But it seems the more you can get up and interrupt this sedentary behavior,the better.”
Figures from a U.S. survey in 20032004 found Americans spend more than half their time sitting,from working at their desks to sitting in cars.
Experts said more research is needed to figure out just how much sitting is dangerous,and what might be possible to offset those effects.
“People should keep exercising because that has a lot of benefits,” EkblomBak said.“But when they’re in the office,they should try to interrupt sitting as often as possible,” she said.
【小題1】What is the best title for the text?
A.Not Sitting Too Much While Working |
B.How to Avoid Sitting Too Much |
C.Sitting Too Much Could Be Deadly |
D.More and More People Sit Too Much |
A.the more time you spend in exercising in a single bout(一回),the healthier you will be |
B.those who often sit too much are sure to grow fat or suffer from a heart attack |
C.regular exercise is effective to get rid of the side effects of sitting too much |
D.you had better not sit for more than four hours in a single bout |
A.It results in a higher death risk. |
B.It increases glucose and fat in the body. |
C.It makes a person unable to exercise long enough in a day. |
D.It causes the gene to fail to balance the glucose and fat in the body. |
A.improve | B.a(chǎn)void |
C.ignore | D.a(chǎn)chieve |
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科目: 來源: 題型:閱讀理解
Did you get a flu shot this year?For the first time,the Centers for Disease Control and Prevention in the US is recommending that all children aged from 6 months to 18 years receive the flu vaccine.
Vaccines battle diseases caused by bacteria and viruses.A weakened form of the germ (病菌) is introduced into the body.The body makes special substances called antibodies (抗體) to fight the germs.If the actual germs were to attack,the antibodies would fight.Because there are many kinds of flu viruses,scientists must create a new vaccine formula (處方) each year.Researchers must make a prediction.
It is like forecasting the weather.Sometimes they are right on,and sometimes they are off.But even when the vaccine does not closely match circulating flu types,it can make the illness less serious.
“The flu vaccine is not as effective as the polio (小兒麻痹癥) vaccine or the measles vaccine,” says Dr.William Schaffner of Vanderbilt University School of Medicine.“It’s not a great vaccine,but it is in fact quite a good vaccine.”
But a flu vaccine doesn’t work for everyone.There are certain people who should be careful about taking it,because the vaccine is produced in eggs.Those who are allergic (過敏的) to eggs should not take it.If you have a fever,you should wait until you recover.
Some people are afraid that they might get the flu from the flu shot.Scientists say that it is not possible,because the viruses in the flu shot are inactivated.But some minor side effects such as lowgrade fever and body ache could occur.If they do,they begin soon after the shot and usually last only one to two days.
Did you know?Smallpox was the first disease people tried to prevent by putting a virus into a healthy person.In 1796,English scientist Edward Jenner placed some infected material under a boy’s skin.
【小題1】The underlined word “vaccine” (in Para.1) refers to________.
A.virus used for fighting against disease |
B.a(chǎn)ntibody to fight the germs |
C.formula to fight against disease |
D.germ to be injected into the body |
A.is as effective as the polio and the measles vaccines |
B.is worse,compared with the polio and the measles vaccines |
C.does help to make illness less serious |
D.is quite good because it works for everyone |
A.those who are not allergic to eggs can take the flu vaccine |
B.not all the flu vaccines are effective for everyone |
C.you should go to a doctor if you have a fever after taking the flu vaccine |
D.it is possible that some people might get the flu from the flu shot |
A.they’ll be allergic to eggs |
B.their bodies will ache for 5 days |
C.they probably have a low fever |
D.they won’t catch a flu ever after |
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科目: 來源: 題型:閱讀理解
Electric cars are dirty.In fact,not only are they dirty,they might even be more dirty than their gasolinepowered cousins.
People in California love to talk about “zeroemissions vehicles”,but_people_in_California_seem_to_be_clueless_about_where_electricity_comes_from.Power plants mostly use fire to make it.Aside from the new folks who have their roofs covered with solar cells,we get our electricity from generators.Generators are fueled by something—usually coal,oil,but also by heat generated in nuclear power plants.There are a few wind farms and geothermal(地?zé)岬? plants as well,but by far we get electricity mainly by burning something.
In other words,those “zeroemissions” cars are likely coalburning cars.It’s just because the coal is burned somewhere else that it looks clean.It is not.It’s as if the California Greens are covering their eyes—“If I can’t see it,it’s not happening.” Gasoline is an incredibly efficient way to power a vehicle;a gallon of gas has a lot of energy in it.But when you take that gas(or another fuel) and first use it to make electricity,you waste a nice part of that energy,mostly in the form of wasted heat—at the generator,through the transmission(傳送) lines,etc.
A gallon of gas may propel your car 25 miles.But the electricity you get from that gallon of gas won’t get you nearly as far—so electric cars burn more fuel than gaspowered ones.If our electricity came mostly from nukes;or geothermal,or hydro,or solar,or wind,then an electric car truly would be clean.But for political,technical,and economic reasons,we don’t use much of those energy sources.
In addition,electric cars’ batteries which are poisonous for a long time will eventually end up in a landfill.And finally,when cars are the polluters,the pollution is spread across all the roads.When it’s a power plant,though,all the junk is in one place.Nature is very good at cleaning up when things are too concentrated,but it takes a lot longer when all the garbage is in one spot.
【小題1】What does the underlined part mean in Paragraph 2?
A.People see the California Greens everywhere. |
B.People in California love to talk about zeroemissions vehicles. |
C.People in California love to have their roofs covered with solar cells. |
D.People in California have no idea that so far electricity mainly comes from burning coal,oil,etc. |
A.Electric cars are not clean at all. |
B.Electric cars are better than gasolinepowered ones. |
C.People cast doubts on electric cars’ batteries. |
D.Gasoline is an efficient way to power a vehicle. |
A.not less than 25 miles |
B.a(chǎn)s far as 50 miles |
C.a(chǎn)s far as 25 miles |
D.not more than 25 miles |
A.being green is good and should be encouraged in communication |
B.electric cars are not clean in that we get electricity mainly by burning something |
C.zeroemissions vehicles should be chosen to protect our environment |
D.electric cars are now the dominant vehicle compared with gasolinepowered cousins |
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科目: 來源: 題型:閱讀理解
I’ve always known my kids use digital communications gear (裝置) a lot.But my cellphone bill last month really grabbed my attention.My son had come up to nearly 2,000 incoming text messages,and had sent nearly as many.Of course,he was out of school for the summer and communicating more with friends from a distance.Nevertheless,he found time to hold down a summer job and complete a college course in between all that typing with his thumb.
I was even more surprised to learn that my son is normal.“Teenagers with cellphones each send and receive 2,272 text messages a month on average,” Nielsen Mobile says.
Some experts regret that all that keyboard jabber is making our kids stupid,unable to read nonverbal cues such as facial expressions,gestures,posture and other silent signals of mood and attitude.Unlike phones,text messaging doesn’t even allow transmission of tone of voice or pauses,says Mark Bauerlein,author of a book called The Dumbest Generation:How the Digital Age Stupefies Young Americans and Jeopardizes Our Future.
Beyond that,though,I’m not sure I see as much harm as critics of this trend.I’ve posted before on how I initially tried to control my kids’ texting.But over time,I have seen my son suffer no apparent ill effects,and he gains a big benefit,of easy,continuing contact with others.
I don’t think texting make kids stupid.It may make them annoying,when they try to text and talk to you at the same time.And it may make them distracted,when buzzing text messages interrupt efforts to noodle out a math problem or finish reading for school.
But I don’t see texting harming teens’ability to communicate.My son is as accustomed to nonverbal cues as any older members of our family.I have found him more engaged and easier to communicate with from a great distance,because he is constantly available via text message and responds with faithfulness and speed.
【小題1】What does the underlined word “distracted” in the fifth paragraph mean?
A.Confused. | B.Absentminded. |
C.Comfortable. | D.Badtempered. |
A.For Teens,Texting Instead of Talking |
B.For Parents,Caring Much for Their Kids |
C.Advantages and Disadvantages of Texting |
D.The Effect of Communication |
A.objective | B.opposed |
C.supportive | D.doubtful |
A.It is normal for a teen to send or receive 60 text messages a day. |
B.Texting is a very popular way of communication among teens. |
C.When texting,teens never mind talking with others. |
D.The writer limited his son to send or receive text messages at first. |
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科目: 來源: 題型:閱讀理解
One of the most popular activities enjoyed by Americans is spending time in forests and walking along paths through the country.This activity,called hiking,has led to the creation of paths throughout the United States.
One of the longest is the Appalachian National Scenic Trail.The trail is the first completed part of the National Trails System.The trails system was established by Congress and the president in 1968.The Appalachian Trail is more than 3,400 kilometers long.It starts in the northeastern state of Maine and ends in the southeastern state of Georgia.The trail goes through 14 states.They are Maine,New Hampshire,Vermont,Massachusetts,Connecticut,New York,New Jersey,Pennsylvania,Maryland,West Virginia,Virginia,Tennessee,North Carolina,and Georgia.
The path takes walkers through the Appalachian Mountains.They extend from the Canadian province of Quebec to the southern American state of Alabama.
The Appalachian Mountains are among the oldest on Earth.They first began forming about one thousand million years ago.During the millions of years since then,the mountains were changed and reformed by the forces of water and wind.Ice also changed the mountains,making many of them smaller and digging valleys and lakes among them.Many different kinds of trees grow along the trail.And many different kinds of animals live in the forests along the trail.
Lands along the trail are protected by the federal government and by state governments.Some parts are not protected by the government directly.Instead,they are protected by legal agreements with private owners willing to permit people to walk across their property.
Walkers on the Appalachian Trail pass through some of the great valley systems of the mountains.They can look down into these beautiful valleys and see farms and forests stretching across the land for many kilometers.Farmland in the valleys is rich and productive.And some of the great events in American history took place in the valleys.For example,one of the great battles of the American Civil War was fought in the Shenandoah Valley in Virginia.
【小題1】The Appalachian Trail________.
A.is more than four thousand three hundred kilometers long |
B.starts in the northern state of Maine |
C.goes through more than fourteen states |
D.ends in the southeastern state of Georgia |
A.a(chǎn)re the first completed part of the National Trails System |
B.began forming one million years ago |
C.were changed by natural forces like water,wind and ice |
D.were around by valleys and rivers and famous for its scenery |
A.a(chǎn)re protected entirely by either the federal government or state governments |
B.a(chǎn)re mainly protected by legal agreements with private owners |
C.can be visited by travelers freely only under the permission of owners |
D.a(chǎn)re protected by both the federal government and state governments |
A.The Appalachian Mountains have some great valley systems. |
B.Farms and grasslands stretch across the valleys for many kilometers. |
C.One of the American independence battles was fought in the Shenandoah Valley. |
D.Lakes in the Appalachian Mountains are one of the most beautiful sights. |
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科目: 來源: 題型:閱讀理解
Plastic is one of the most important technological discoveries of the 20th century.However,it may soon be replaced.The new development—liquid wood—can replace plastics in all branches of modern industries.
Plastic as a material enjoys the biggest demand in the modern world,but it does have a number of drawbacks.First and foremost,plastic isn’t recyclable.Secondly,it contains toxins (毒物) helping develop cancerous diseases.Finally,it’s made of oil and oil reserves aren’t endless.
The liquid wood technology is likely to replace plastic and provide mankind with new materials for many years ahead.Norbert Eisenfreich,a senior researcher at the Faunhofer Institute for Chemical Technology (ICT) in Germany,said that arboform,the new material,is made of lignin (木質(zhì)素),which can be obtained from soft tissues of wood.Once mixed with several other materials,it turns into solid and nontoxic alternative for plastics.
ICT team leader Emilia Regina InoneKauffmann said the woodworking industry separates wood into three basic components,including lignin.Lignin isn’t used for the production of paper.Specialists of ICT mixed lignin with several natural materials and thus invented the material which could be melted and molded (鑄型).
When solid,arboform looks like plastic and possesses the qualities of polished wood.It can be used for the production of any items.Arboform is already used for the production of car parts which require extra strength.In addition,liquid wood can be recycled repeatedly.The material preserved all of its qualities even if it’s reprocessed ten times.
However,the new invention doesn’t enjoy an extensive use due to the high content of sulphur (硫) in it.German researchers are sure to reduce the amount of sulphur by 90 percent very soon to make arboform usable for home needs.
【小題1】According to the passage,plastic________.
A.plays a big role in the modern world |
B.helps to protect our environment in some way |
C.has been replaced by the newly discovered material |
D.helps us to reduce the use of petrol |
A.It is easily made from natural oil. |
B.It is more widely used in household. |
C.It is recyclable and friendly to the environment. |
D.It contains no poisonous materials. |
A.the material’s extensive use |
B.the content of sulphur in arboform |
C.the production cost of arboform |
D.the qualities of liquid wood |
A.a(chǎn)dvertise the new material—arboform |
B.introduce liquid wood which will replace plastic |
C.a(chǎn)dvertise new products made of arboform |
D.show readers how to produce arboform |
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科目: 來源: 題型:閱讀理解
Disposing(處理)of waste has been a problem since humans started producing it.As more and more people choose to live close together in cities,the waste-disposal problem becomes Increasingly difficult.
During the eighteenth century,it was usual for several neighboring towns to get together to select a faraway spot as a dump site.Residents or trash haulers(垃圾拖運(yùn)者)would transport household rubbish,rotted wood,and old possessions to the site.Periodically(定期的)some of the trash was burned and the rest was buried.The unpleasant sights and smells caused no problem because nobody lived close by.
Factories,mills,and other industrial sites also had waste to be disposed of.Those located on rivers often just dumped the unwanted remains into the water.Others built huge burners with chimneys to deal with the problem.
Several facts make these choices unacceptable to modern society.The first problem is space Dumps,which are now called landfills,are most needed in heavily populated areas.Such areas rarely have empty land suitable for this purpose.Property is either too expensive or too close to residential(住宅區(qū)的) neighborhoods.Long-distance trash hauling has been a common practice but once farm areas are refusing to accept rubbish from elsewhere,cheap land within trucking distance of major city areas is almost nonexistent.
Awareness(意識(shí)) of pollution dangers has resulted in more strict rules of waste disposal. Pollution of rivers,ground water,land and air is a price people can no longer pay to get rid of waste. The amount of waste,however,continues to grow.
Recycling efforts have become commonplace,and many towns require their people to take part.Even he most efficient recycling programs,however,can hope to deal with only about 50 Percent of a city’s reusable waste.
【小題1】The most suitable title for this passage would be _______.
A.Places for Disposing Waste | B.Waste Pollution Dangers |
C.Ways of Getting Rid of Waste | D.Waste Disposal Problem |
A.burying it | B.recycling it |
C.burning it | D.throwing it into rivers |
A.Farm areas accept waste from the city in modern society. |
B.There is cheap land to bury waste in modern society. |
C.It is difficult to find space to bury waste in modern society. |
D.Ways to deal with waste in modern society stay the same. |
A.draw people’s attention to waste management |
B.warn people of the pollution dangers we are facing |
C.call on people to take part in recycling programs |
D.tell people a better way to get rid of the waste |
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科目: 來源: 題型:閱讀理解
Men have always believed that they are smarter than women. Now, a study has found that while this is certainly true, men also have to deal with the fact that they are also more stupid than the fairer sex.
In the study, scientists measured the IQ of 2500 brothers and sisters and they found an uneven number of men not only in the top two percent, but also in the bottom two percent.
The study's participants were tested on science, maths, English and mechanical abilities.
Though there were twice as many men as women in the smartest group, there were also twice as many men among the dolts.
The aggregate scores of men and women were similar.
One of the study's authors, psychology professor Timothy Bates, said that the phenomenon may be because men have always been expected to be high achievers and women have been restricted to spend more time taking care of their home.
"The female developmental program may be tilted more towards ensuring survival and the safety of the middle ground.," the Daily Mail quoted Professor Bates, of Edinburgh University, as saying.
The research tallies with past results that men were more likely than women to receive first class University degrees or thirds and women secured the seconds.
It has been said that men are more ready to take risk when it comes to academics. Women have always found to be steadier in their learning.
A past study has shown that women are securing more firsts and seconds, while men are continuing to receive more thirds.
The argument for the change is that the increase of coursework at the cost of exams favors women's steady approach.
【小題1】The purpose of the passage is to tell us that ________.
A.man are smarter then women |
B.man are more stupid the women |
C.a(chǎn) new fact about the IQ of men and women has been found |
D.men are more likely to receive first class university degrees |
A.they are born stupid |
B.they have to spend more time to tale care of their home than men |
C.they don’t like to take risk |
D.they are not expected to be high achievers |
A.a(chǎn)gree with | B.deal with | C.go against | D.go with |
A.Women are steadier in their learning. |
B.men are more ready to take risk in everything |
C.women are securing more firsts and seconds |
D.women are doing much better in academy |
A.Why are men smarter than women? |
B.Why are men more stupid than women? |
C.How does the result go along with the past research? |
D.How can we help the men in the bottom? |
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