题目内容

It’s a sure sign that summer is over and winter is on the way — leaves that were once deep green turn red, yellow and bright orange. It happens every autumn. But did you ever wonder why?

The leaves start changing color when the nights start getting longer and the temperature starts getting cooler. Some scientists think that as the number of daylight hours shrinks, the leaves stop making chlorophyll which makes plants green. The reason is that the process of making chlorophyll requires sunlight. But according to horticulture (园艺) educator Susan Rose from Colorado State University, it turns out leaves don’t really change color at all. “The fall colors are actually there all along,” she said. “But they are covered by the green chlorophyll. As the chlorophyll stops being produced, the other colors can shine through.”

The kind of color that the leaves are going to change to is determined by the plant’s genetic (基因的) background. In some places, the leaves start changing color in September — before autumn even officially begins. In other places, they don’t change until late October or even November. Some scientists say the leaves have been changing color later than usual in recent years. And they think global warming has something to do with that.

In one study, researchers found that the growing season in the Northern Hemisphere was nearly a week longer, on average, in 2008 than it was in 1982. And a professor from Harvard University found that the leaves, west of Boston, Massachusetts, are changing color about three days later than they used to. However, other scientists disagree with the global warming theory. Susan Rose said the leaves in her part of Colorado are changing “right on schedule.” But the leaves in other parts of that state are running a little late. “The lateness in the mountains may have something to do with the really warm late summer and early fall,” she said. “But I’m afraid that’s just a guess.”

1.According to Susan Rose, _____.

A.the fall colors are always in leaves

B.leaves make chlorophyll all the seasons

C.leaves’ changing color have nothing to with the weather

D.leaves begin changing color because they start making chlorophyll

2.The underlined word “shrinks” in Paragraph 2 could best be replaced by _____.

A.reduces          B.increases          C.lasts              D.appears

3.Scientists guess leaves change color later than usual probably as a result of _____.

A.genetic background                     B.dry weather

C.global warming                         D.low temperature

4.The purpose of the last paragraph is to tell readers _____.

A.why leaves change color at fall

B.leaves change color at different time

C.the effects of the global warming on plants

D.different opinions on the lateness of leaves’ changing color

 

【答案】

1.A

2.A

3.C

4.D

【解析】

试题分析:文章介绍秋天树叶变颜色的原因,还有现在树叶变绿的时间比以前迟了,科学家认为主要是因为全球气温变暖造成的,还有科学家给出不同的解释。

1.细节题:从第二段的句子:“The fall colors are actually there all along,” she said. “But they are covered by the green chlorophyll. 可知秋天的颜色一直在树叶里面。选A

2.猜词题:从后面的句子:the leaves stop making chlorophyll which makes plants green. 可知白天时间减少后,树叶就不再产生会使树变绿的chlorophyll ,选A

3.细节题:从第三段的句子:And they think global warming has something to do with that.可知科学家认为现在树叶变绿的时间比以前迟了,主要是因为全球气温变暖造成的。选C

4.细节题:从最后一段的句子:“The lateness in the mountains may have something to do with the really warm late summer and early fall,”可知最后一段是给出关于树叶变颜色推迟的不同解释,选D

考点:考查科普类短文

点评:本文属于科普文章,介绍秋天树叶变颜色的原因,还有现在树叶变绿的时间比以前迟了,科学家认为主要是因为全球气温变暖造成的,还有科学家给出不同的解释。细节题居多,答题时在文章找到对应的地方,用笔进行标记,这有利于后期有时间检查时可以立刻找到答案的位置。仔细理解作者所讲的意思,再结合选项,通过排除法和自己对全文的把握,选出正确答案。

 

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An annoying problem for humans, who like to boast (夸耀) about all the distant planets and moons we have explored, is that we've never taken a good look right under our noses.The inside of the earth is relatively close but how can we get there?

The deepest oil well enters a mere six miles into the crust (地壳)  (the center of the earth is about 4,000 miles deeper).Russian scientists dug the deepest hole in Siberia," but bottomed out at about 7.5 miles below the surface.The Mohole project, a U.S.plan in the 1950s, called for drilling a hole 25 miles down to the boundary be??tween the hard rocks of the crust and the soft mantle (地幔).Sadly the project involved govern??ment supporting.

It gets harder and harder to drill deep into the earth because rocks get softer and softer. Hard but easily broken at the surface, rocks become plastic at depth, and the pressure caused by the weight of the overlaying crust — about 52,800 pounds per square inch at a depth of ten miles, makes further drilling impossible.

What little we know about the inside of the earth (like the fact that there' s a crust, a mantle, and a core) comes from indirect evidence, such as the analysis of earthquakes.

So maybe it' s time for a thorough new method to explore the earth's inside.Scientist David Stevenson says we should forget about drilling holes.Instead, we should open a crack (裂缝). 

Stevenson suggests digging a crack about a half mile long, a yard wide, and a half mile deep (not with a shovel) but with an explosion on the scale of a nuclear bomb.Next, he'd pour a few hundred thousand tons of molten (融化的) iron into the crack, along with a robot.The iron, thicker than the surrounding crust, would move downward at about 16 feet per second, carrying the robot with it and opening the crack deeper and deeper.The iron mass would drop for about a week and 2,000 miles to the outer edge of the earth core, the robot sending out data to the sur??face.

Stevenson compares his idea to space explo??ration."We're going somewhere we haven't been before," he says."In all possibility, there will be surprises."

This idea can probably be put in.the drawer marked with Isn't Going To Happen.The robot would have to survive temperatures that would melt pretty much anything.But Stevenson's idea may inspire a new look at an old problem.Great things can come from what seems like impossible ideas.

Going inside the earth is ________ than going into space.

A.more interesting B.more possible    C.easier            D.more challenging

How deep have we gone into the earth until now?

A.6 miles.         B.4,000 miles. C.7.5 miles.        D.25 miles.

Which of the following is TRUE about David Stevenson's idea?

A.It is an inspiring but not practical idea now.

B.It is a practical proposal that has come into use now.

C.It is a good proposal that will soon be put into practice.

D.It is a false theory that cannot be carried out at all.

What might be the most suitable title for the text?

A.An Annoying Problem for Humans

B.To the Center of the Earth

C.The Mohole Project

D.David Stevenson' s Proposal

Australian scientists are trying to give kangaroo-style stomachs to cattle and sheep in order to cut he greenhouse gases they send out, which are thought to be responsible for global warming.

Thanks to special bacteria in their stomachs, kangaroo flatulence(肠胃气胀)contains no methane(甲烷)and scientists want to transfer that bacteria to cattle and sheep who produce large quantities of the harmful gas.

While the usual image of greenhouse gas pollution is a billowing smokestack (烟囱) pushing out carbon dioxide, farm animals’ passing wind contribute a sur­prisingly high percentage of total emissions (排放物)in some countries.

“Fourteen percent of emissions from all sources in Australia are from enteric methane from cattle and sheep,” said Athol Kleve, a senior research scientist with the Queensland state government.

“And if you look at another country such as New Zealand, which has got a much higher agricultural base, they're actually up around 50 percent, ” he said.

Researchers say the bacteria also make the diges­tive process much more efficient and could potentially save millions of dollars in feed costs for farmers.

But it will take researchers at least three years to isolate (分离) the bacteria, before they can even start to develop a way of transferring it to cattle and sheep.

Another group of scientists, meanwhile, has suggested Australians should farm fewer cattle and sheep and just eat more kangaroos.      

The idea is controversial (有争议的), but about 20 percent of health-conscious Australians are believed to eat the national symbol already.

“It's low in fat, it’s got high protein levels and it's very clean in the sense that basically it's the free-range (放养的) animal,” said Peter Amp of the University of New South Wales's institute of environmental studies.

1.Scientists intend to put bacteria into cattle and sheep _________.

A. so that they can make full use of special bacteria

B. to help Australian farmers to earn more money

C. so that they can protect Australian ecosystem

D. to prevent them from sending out harmful gases

2.Athol Kleve seems to believe that ________.

A. cattle and sheep produce more carbon dioxide

B. less cattle and sheep are raised in New Zealand

C. farm animals are responsible for greenhouse gases

D. New Zealand has the most animals in the world

3.What do the underlined words “the idea” in para­graph 9 refer to?

A. Australians should farm fewer cattle and sheep and just eat more kangaroos.

B. The bacteria could make the digestive process much more efficient.

C. Australians should give kangaroo - style stomachs to cattle and sheep.

D. The bacteria could save millions of dollars in feed costs for farmers.

4.Which of the statements is the advantage Peter Amp lists about kangaroo?

A. it is rich in protein                                    B. it is cheaper than beef

C. it is high in fat                                                       D. it is more delicious than sheep

 

阅读理解。
     The Couch Surfing network is an online community stretching across the globe with over one and a
half million members. The basic concept is to provide a platform for travelers to contact people who are
willing to put them up free of charge. Travelers connect with potential hosts online and, if they like each
other, exchange details to make further arrangements.
     Basil is one traveler from Switzerland who is currently couch surfing with a Chinese host in Beijing.
"I thought staying in hostel is nice but you mostly meet foreigners and speak English. If you use Couch.
Surfing
you have chance to meet people living here and really get a chance to know the life of the place
you visit." Basil was speaking during a regular meeting of the Beijing network of Couch Surfing with a
membership of almost 2 000.
     Although some people may have concerns about meeting complete strangers and giving them full access
to your house, Beijing group member Fred Sharp from California says that the Couch Surfing community
is one that generally attracts trustworthy people.
     "I have never had a problem with guests. I'd say that this Couch Surfing community worldwide is a fairly
trustworthy community. Like I say, always be cautious, make sure that you read everyone's profile that you
re considering hosting, and if it doesn't feel right just say 'no', it's ok."
     Originally launched in the US as a non-profit organization in 2004, Couch Surfing is growing fast across
the world. China is no exception with around 30 000 members and hundreds more signing up each week.
One of them is Beijing resident Hai Yan who joined in November 2009. She says the first time she hosted a
guest was a very positive experience. "My first guest was from Italy. He was very kind and helpful. He
bought me a present from Italy, a handbag. It's a famous brand!"
     As the organization grows from strength to strength, hotel owners across the world will be watching
very closely and possibly thinking twice about raising their prices too high.
1. The Couch Surfing network is intended to _____.
[     ]
A. give reliable information about hotels
B. provide people with a platform to contact each other
C. find potential hosts who want to supply travelers with couches
D. offer travclers convenience to find suitable hosts for free accommodations
2. According to Fred Sharp, _____.
[     ]
A. couch surfers can fully rely on Couch Sur fing community
B. Couch Surf ing community enables you to meet different people
C. Couch Surfing community is trusted by all couch surfers
D. couch suffers may form a judgment on hosts and make a final decision
3. We can infer from the passage that _____.
[     ]
A. Couch Surfing has a long history
B. Hai Yan is satisfied with her host
C. Couch Surfing is getting popular in China
D. Basil works at the Beijing Network
4. The last paragraph suggests that hotels will _____.
[     ]
A. be replaced by the organization
B. probably not charge too much
C. not consider raising their prices
D. show no concern about the organization

Until the 1960's, almost everyone in the U. S. followed tradition and gave all the children in the same family the same last name or surname, as it is called. But during the 60's, young parents began giving their children strange names—names like Moonglow, Eternal Peace, and Sunshine. Some states passed laws controlling the names that parents could use. But after a court case in 1981, a federal judge ruled that parents are free to give any surnames they wish to their children.

So , for the last few decades , more parents are not giving their children the fam­ily 's sur- names .Some insist that while it ' s OK for a boy to have the father ' s family name, a girl should have the mother' s family name . Thus, Philip Gaylord and Pan Zimmitti could be brother and sister. Some parents think that using family surname is old —fashioned and boring. One couple gave their son the last name Sue because they like the Johnny Cash song," A Boy Named Sue." And finally, some parents think that giving their children different surnames is just a "neat thing to do". So the first son of a New York family has the last name Washington —Lincoln, after the two fa­mous presidents. The daughter has the last name Anthony—Tubman after two women who fought for women's rights.

This change in naming customs presents two problems. First, if each person in the family has a different last name, family records will be very confusable. It will be hard to track a person's family, and record keeping will be difficult .Second, some physiologists are afraid that different surnames will threaten family unity. Since names have  an important effect on one's identify (身份) , they think brothers and sisters will not feel connected if they have different last names.

So this problem of names will get worse as new and different last names increase. Get ready to meet Welcome Baby Darling , sister of Aren't We Glad , You ' re Here and It ' s About Time.

1.In America, ________to give children different surnames these days.

    A.it is allowed by the law                  B.it breaks the law

    C.it is one of the customs                  D.it is unusual

2.In the second paragraph of the passage a "neat thing to do" means________.

    A.a good thing to do                                                  B.a terrible thing to do

    C.a dirty filing to do                   D.a clean thing to do

3.According to some psychologists, the different last names will let brothers and sisters feel they

are________.

    A.enemies                          B.as close as before

    C.good fiends                       D.separated

4.From the last paragraph, we can see the author _____this change in naming customs.

       A.is for        B.is against          C.doesn't care         D.doesn't notice

Picnicking in special places throughout the US has become a choice for many people. We’ve come up with 5 of the top picnicking areas across the US.

Cumberland Islands, Georgia

This national shore(海岸) is a perfect picnicking place. It’s an undamaged place in the Deep South with over 50 miles of hiking trails(小径) and beaches. The trails are lined with trees covered in Spanish moss.

Grant Park, Chicago

If you are looking for delicious food in Chicago, go for taste of a 20-day, lake-front foodie festival that happens each year. Grab a spot near the fountain to enjoy your picnic, appreciate the city scenery and lake views and relax. If you are there on July 4th, be sure to plan the day to include the firework display at the Navy Pier.

Cranberry Islands, Maine

Here, you’ll find natural picnicking with island views. The islands are a delightful group of islands about 20minutes by private boat or ferry service. Bring a picnic basket along for the ride as it’s a romantic picnic area to take your friends or go for a family outing to visit the islands. You can visit the Islands by private boat or ferry service.

Red Rock Canyon, Nevada

If you happen to be in Las Vegas, Red Rock Canyon and the nearby Spring Mountain Ranch State Park offer a welcome rest. Situated just 19 miles west of Vegas, it’s a trip worth taking. There are plenty of picnic areas along the drive and in nearby Spring Mountain Ranch State Park which also offers outdoor theaters and concerts in summer months.

Big Sur, California

The Point Lobos State Reserve has often been called “ the crown(皇冠) jewel of the State Park System”. Besides the coastal wildlife, there are rare plant communities and unique geological formations(地质构造)。It’s good for you to have a picnic in the reserve. We recommend bringing a telescope, because much of the wildlife can be seen only at a distance.

56. In which state will there be the firework display on the National Day?

A. Georgia.  B. Chicago   C. Maine   D. California

57. We can infer from this passage that___.

A. you can see wild animals in the cages in Red Rock Canyon.

B. there is a half-a- month foodie festival every year in Grant Park.

C. the Point Lobos State Reserve is often considered as the best in the park.

D. the national park has something to do with strawberries.

58. What’s the author’s purpose in writing the passage?

A. To introduce some picnicking areas.

B. To attract more people to visit these places.

C. To tell readers how to appreciate the parks.

D. To show the pleasure in these attractions.

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