The leader o did not realize the problem and did nothing with it.——青夏教育精英家教网—

The leader o did not realize the problem and did nothing with it. 【查看更多】

题目列表(包括答案和解析)

Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly.

A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic snow were declining.

In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States.

In a study published in the journal Ambio, scientists found that lead levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline.

Many scientists had believed that the lead would stay in soil and snow for a longer period.

The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected.

Scientists say both studies demonstrate that certain parts of the ecosystem respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute.

57.　 The study published in the journal Nature indicates that ________.

A.　 the Clean Air Act has not produced the desired results

B.　 lead deposits in arctic snow are on the increase

C.　 lead will stay in soil and snow longer than expected

D.　 the US is the major source of lead pollution in arctic snow

58.　 Lead accumulation worldwide decreased significantly after the use of unleaded gas in the US　 _____ .

A.　 was discouraged B.　 was enforced by law

C.　 was prohibited by law　　　　　 D.　 was introduced

59.　 How did scientists discover the source of lead pollution in Greenland?

A.　 By analyzing the data published in journals like Nature and Ambio.

B.　 By observing the lead accumulations in different parts of the arctic area..

C.　 By studying the chemical elements of soil and snow in Northeastern America.

D.　 By comparing the chemical compositions of leaded gasoline used in various countries.

60.　 The authors of the Ambio study have found that ________.

A.　 forests get rid of lead pollution faster than expected

B.　 lead accumulations in forests are more difficult to deal with

C.　 lead deposits are widely distributed in the forests of the US

D.　 the upper layers of soil in forests are easily polluted by lead emissions

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阅读理解

　　It takes more than just practice to become an Olympian．Gold medal performances require some serious nutrition．Have you ever wondered what these successful athletes eat to stay in peak shape?

　　Keri Glassman, a registered dietitian and founder of Nutritious Life Meals, appeared on “Good Morning America” today to give you a glimpse into the diets of some top athletes．Some of their meals could surprise you．

　　Crazy Calorie Count

　　Glassman said Olympians eat a lot of food－ quantities that for ordinary people would constitute pigging out．One secret of swimmer Michael Phelps' astonishing performance in the 2008Olympics in Beijing was consuming as many as 12,000 calories in one day．

　　Athletes can eat like this and not gain any weight because their workouts are intense．According to Glassman, Phelps' workouts can burn 4,000 to 6,000 calories in a day, and those calories must be added in order to train the following day．

　　Snacking Secrets

　　Some athletes eat strange foods that improve their performance．Yohan Blake, the Jamaica sprinter and 100-meter world champion, has stolen champion sprinter Usain Bolt's thunder on the track during the Olympic trials, Asked about how he gets his energy．Blake answered that he eats 16 bananas per day,Glassman said．

　　Jonathan Horton, the lead gymnast on the US team, has a blood sugar problem．His solution is honey．When he starts to feel shaky at the gym, he takes honey to boost his energy, Classman said．

　　Foods for Recovery

　　What are the best foods to help the body recover after harsh competition?

　　For Olympic swimmer Ryan Lochte, the recovery meal is grilled chicken breasts with Alfredo sauce, whole-grain spaghetti and a salad with lemon juice and olive oil．Lochte, who recently cut out junk food, candy and soda, has undertaken a strength-training regimen(养生法)that involves flipping tractor tires, and tossing beer kegs, Glassman said．

(1)

What's the best title of this passage?
[　　]
A．	Good Diet Makes a True Olympian．
B．	Olympians Have Olympic-size Appetites．
C．	Olympians'Strange Eating Habits．
D．	The Diet of Some Top Olympic Athletes．

(2)

What does the underlined sentence probably mean?
[　　]
A．	Ordinary people eat few pigs compared with Olympians．
B．	Olympians eat a lot more food than ordinary people．
C．	Olympians tend to eat a lot of high-quality food．
D．	Olympians eat a large amount of food, just like pigs．

(3)

Which of the following is TRUE according to the passage?
[　　]
A．	Ryan Lochte quit eating junk food, candy and soda for his better recovery．
B．	Yohan Blake finally beat Usain Bolt in the 100-meter track in the Olympics．
C．	Michael Phelps'astonishing performance was due to his eating lots of food．
D．	Jonathan Horton has a blood sugar problem because of taking too much honey．

(4)

Which of the following is not the best food to help the body recover?
[　　]
A．	Soda．
B．	Olive oil．
C．	Whole-grain spaghetti．
D．	A salad with lemon juice．

(5)

The passage is most likely to be found in．
[　　]
A．	a technical report
B．	a fashion magazine
C．	an education column
D．	a sports newspaper

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听下面5段对话。每段对话后有一个小题，从题中所给的A，B，C三个选项中选出最佳选项，并标在试卷的相应位置。听完每段对话后，你都有10秒钟的时间来回答有关小题和阅读下一小题。每段对话仅读一遍。

1．What color is the woman's car?

[　　]

A．Red.

B．Blue.

C．Green.

2．How long will they have to wait?

[　　]

A．2 hours.

B．4 hours.

C．We don't know.

3．Why isn't the man going to work?

[　　]

A．He is ill.

B．He will play golf with Bob.

C．His boss is ill.

4．Where is the woman?

[　　]

A．In Washington.

B．In Chicago.

C．In Miami.

5．How did the woman know about the fire?

[　　]

A．She saw it.

B．Others told her.

C．She heard it over the radio.

听下面5段对话或独白。每段对话或独白后有几个小题，从题中所给的A，B，C三个选项中选出最佳选项，并标在试卷的相应位置。听每段对话或独白前，你将有时间阅读各个小题，每小题5秒钟；听完后，各小题将给出5秒钟的作答时间。每段对话或独白读两遍。

听第6段材料，回答第6－8题。

6．What are they talking about?

[　　]

A．A live concert.

B．A record.

C．Some singers.

7．What do they think of it (them)?

[　　]

A．Good.

B．Not good.

C．Not bad.

8．What caused the trouble?

[　　]

A．The lead singer.

B．The loud sound of guitars.

C．They're not a famous group.

听第7段材料，回答第9－11题。

9．What does the woman think Bill's problem is?

[　　]

A．He sometimes disobeys.

B．He doesn't always do his homework.

C．He needs glasses.

10．Which grade is Bill in?

[　　]

A．Fourth.

B．Fifth.

C．Sixth.

11．What subject is Bill having trouble in?

[　　]

A．Science.

B．Writing.

C．Reading.

听第8段材料，回答第12－14题。

12．Why did the woman want to change job?

[　　]

A．She wanted a job as a waitress.

B．She wanted more time to study.

C．Her pay was too low.

13．What days did the man say they needed help?

[　　]

A．At weekends.

B．On weekdays.

C．Late in the week.

14．What was the result of the interview?

[　　]

A．She got the job.

B．She was able to enter the university.

C．The man promised her a pay rise.

听第9段材料，回答第15－17题。

15．What is the woman doing?

[　　]

A．Looking for volunteers.

B．Looking for a baby-sitter.

C．Cooking food.

16．What does the man suggest that he might be willing to do?

[　　]

A．Change diapers.

B．Be a playground assistant.

C．Help the woman sell some candies.

17．What does the man describe as a benefit of volunteering?

[　　]

A．The man will feel better about himself.

B．The man will be able to play with the children.

C．The man will get a free breakfast.

听第10段材料，回答第18－20题。

18．What surprised the people?

[　　]

A．That he was killed in a peaceful place.

B．The local newspaper.

C．Japan's over-strict education system.

19．What can be inferred about the killer?

[　　]

A．He is a teacher.

B．He is a student.

C．He is an education expert.

20．What can we learn about Japanese young students?

[　　]

A．They are under high pressure.

B．They can take care of others.

C．They are very rude and violent.

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阅读理解：

　　Our boat floated on, between walls of forest too thick to allow us a view of the land we were passing through, though we knew from the map that our river must from time to time be passing through chains of hills which crossed the jungle plains．Nowhere did we find a place where we could have landed：where the jungle did not actually spread right down into the river, banks of soft mud prevented us going ashore．In any case, what would we have sailed by landing?The country was full of snakes and other dangerous creatures, and the jungle was so thick that one would be able to advance only slowly, cutting one’s way with knives the whole way．So we stayed in the boat, hoping we reached the sea, a friendly fisherman would pick us up and take us to civilization．

　　We lived on fish, caught with home-made net of string(we had no hooks), and fruits and nuts we could pick up out of the water．As we had no fire, we had to eat everything, including the fish, raw I had never tasted raw fish before, and I must say I did not much enjoy the experience; perhaps sea fish which do not live in the mud are less tasteless．After eating my raw fish, I lay back and dreamed of such things as fried chicken and rice, and ice-cream．In the never-ending damp heat of the jungle, ice-cream was a particularly frequent dream．

　　As for water, there was a choice：we could drink the muddy river water, or die of thirst．We drank the water．Men who had just escaped what had appeared to be certain death lose all worries about such small things as diseases caused by dirty water．In fact, none of us suffered from any illness as a result．

　　One day we passed another village, but fortunately nobody saw us．We did not wish to risk being taken prisoners a second time：we might not be so lucky to escape in a stolen boat again．

(1)

What they could see in the boat was only ________．
[　　]
A．	high wall
B．	villagers from time to time
C．	vast land
D．	heavy woods

(2)

They couldn’t land because ________．
[　　]
A．	the mud on the shore was too soft
B．	the forest was too thick to let them go through
C．	they could not find the mark on the map
D．	they could not find anyone to lead them out of the forest

(3)

The passage infers that the forest was ________．
[　　]
A．	rich of fruits and animals to be served as food
B．	not very thick as they could advance slowly by cutting the branches
C．	full of various dangerous beings
D．	full of ancient trees

(4)

The most proper title for this passage might be ________．
[　　]
A．	Escape
B．	Scenes of a River
C．	How to Survive on a boat
D．	A New Experience

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阅读理解

　　In the atmosphere, carbon dioxide acts rather like a one-way mirror or the glass in the roof of a greenhouse which allows the sun's rays to enter but prevents the heat from escaping．

　　According to a weather expert' s prediction, the atmosphere will be 3℃warmer in the year 2050 than it is today, if man continues to burn fuels at the present rate．If this warming up took place, the ice caps in the poles would begin to melt, thus raising sea level several metres and severely flooding coastal cities．Also, the increase in atmospheric temperature would lead to great changes in the climate of the northern hemisphere(北半球), possibly resulting in an alteration of the earth's chief food growing zones．

　　In the past, concern about a man-made warming of the earth has concentrated on the Arctic because the Antarctic is much colder and has a much thicker ice sheet．But the weather experts are now paying more attention to West Antarctic, which may be affected by only a few degrees of warming, in other words, by a warming on the scale that will possibly take place in the next fifty years from the burning of fuels．

　　Satellite pictures show that large areas of Antarctic ice are already disappearing．The evidence available suggests that a warming has taken place．This fits the theory that carbon dioxide warms the earth．

　　However, most of the fuel is burnt in the northern hemisphere, where temperatures seem to be falling．Scientists conclude , therefore, that up to now natural influences on the weather have gone beyond those caused by man．The question is：Which natural cause has most effect on the weather?

　　One possibility is the variable behavior of the sun．Astronomers at one research station have studied the hot spots and "cold" spots(that is, the relatively less hot spots)on the sun．As the sun rotates(使旋转), every 27.5 days, it presents hotter or "colder" faces to the earth, and different aspects to different parts of the earth．This seems to have a considerable effect on the distribution of the earth's atmospheric pressure, and consequently on wind circulation．The sun is also changeable over a long term：its heat output goes up and down in cycles, the latest trend being downward．

　　Scientists are now finding shared relations between models of solar weather interactions and the actual climate over many thousands of years, including the last Ice Age．The problem is that the models are predicting that the world should be entering a new Ice Age and it is not．One way of solving this theoretical difficulty is to assume a delay of thousands of years while the solar effects overcome the inertia(惯性)of the earth's climate．If this is right, the warming effect of carbon dioxide might thus be serving as a useful opposed balance to the sun's fading heat．

(1)

It can be concluded that a concentration of carbon dioxide in the atmosphere would ________．
[　　]
A．	mean a warming-up in the Antarctic
B．	raise the temperature of the earth' s surface
C．	prevent the sun's rays from reaching the earth's surface
D．	explain the cause of great changes in the climate in the northern hemisphere

(2)

The article was written to explain ________．
[　　]
A．	the greenhouse effect
B．	the solar effects on the earth
C．	the causes affecting weather
D．	the models of solar-weather interactions

(3)

Although the fuel consumption is greater in the northern hemisphere, temperatures there seem to be falling．This is ________．
[　　]
A．	mainly because the levels of carbon dioxide are rising
B．	partly due to changes in the output of solar energy
C．	possibly because the ice caps in the poles are melting
D．	only due to the effect of the inertia of the earth' s climate

(4)

On the basis of their models, scientists believe the opinion that ________．
[　　]
A．	the climate of the world should be becoming cooler
B．	the new Ice Age will be delayed by the greenhouse effect
C．	the man-made warming effect helps to increase the solar effects
D．	it will take thousands of years for the inertia of the earth's climate to take effect

(5)

If the assumption about the delay of a new Ice age is correct, ________．
[　　]
A．	ice would soon cover the northern hemisphere
B．	the greenhouse effect could work in favor of the earth
C．	the best way to overcome the cooling effect would be to burn more fuels
D．	the increased levels of carbon dioxide in the atmosphere could warm up the earth even more quickly

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