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 have suggested that fire in northern regions speed up climate warming because greenhouse gases from burning trees and plants are released into the atmosphere and thus trap 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 ash from the fire fell on far-off 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 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.

46. According to the new findings, taking steps to prevent northern forest fires may __________.

A. result in a warming climate     

B. cause the forest fires to occur more frequently

C. lead to a longer fire season             

D. protect the forests and the environment there

47. The following are all the immediate effects after a forest fire EXCEPT __________.

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. ashes from the fire fall on the ice surface and take in more radiation from the sun

48. Earlier studies about northern forest fires __________.

A. analyze all aspects of how northern fires influence climate

B. indicate that forest fires will pollute the atmosphere

C. suggest that people should take measures to protect environment

D. suggest that the fires will speed up climate warming

49.The underlined phrase “soak up” in the last paragraph most probably means __________.

A. released         B. absorbed       C. created      D. distributed

50. From the passage we can draw a conclusion that forest fires in Alaska, Canada and Siberia may __________.

A. warm the climate as the supposition goes

B. allow more snow to reflect more sunlight into space and thus cool the climate

C. destroy large areas of forests and pollute the far-off sea ice

D. help to gain more energy rather than release more energy

Her frozen fingers touched the flame trying to feel alive. She could feel the warmth but it was a cold heat, as if the candle was rejecting her.

Her arms turned red because of the cold, her short sleeved shirt not giving her enough warmth. The winter air grabbed(抓住) at her arms, causing her pain, but she didn’t mind. She knew she should put her jacket on, it was winter in Connecticut, but that would be giving up. Up here, in this tree she felt safe.

She looked at the candle, surrounded by hardening wax(蜡). She placed her fingers gently on the warm green wax. This candle was a reminder of her life inside that house, a life she would have to return to eventually.

As a child, she had gotten this candle. She spent all she had on it. The beautiful crystal box （水晶盒）had caught her eye. Five whole nickels（五分币） had brought her that candle.

She gave it to her mother for Mother’s Day. Her mother had managed a smile and put it on a shelf. “It’s very pretty, honey! I will put it right here.” Since then that candle had never been moved, never been lighted, sitting dusty on a cluttered shelf that no one could see. Later on, her parents got divorced.

By now the candle was colder than the air and the darkness was complete. The snow on the ground made the night lighter and less satisfying than it had been before the first snowfall. She liked the darkness because she felt safe in it. From the glances of her friends who liked the girl she used to be. From the boys who could never figure out who she was. From her guidance counselor(顾问) whose endless worried looks never made her feel any better.

No one was outside at this time of night. She was alone in the world, just how she liked it. Just as she was about to lean back against the branch, she heard a sound.

She heard footsteps breaking the ice in the snow, heading toward her. He was making his way toward the white fence at the edge of the building, right against the road. Normally she would have ignored this person and stayed on her branch faraway from human contact, but this figure had something with him. He trudged(吃力地走) toward the white fence carrying a case. The figure reached the fence, opened the case and took out a shiny object.

She took her eyes off this figure only long enough to climb down the tree to get a better view of him. She reached the bottom and saw that the person had turned to face the street, sitting on the white fence that she and her friends once sat on. She stepped carefully on the ice, making her way toward him.

And then a beautiful sound of music came from the shiny object. She stopped and listened to it. She started walking towards the guy again. Just as she was about to step onto the snow banks, she slipped on the ice crashing to the ground. The figure turned around in surprise and a sudden recognition fell upon them both.

1.The girl was hiding in the tree at deep night to ______.

A．keep herself from the cold                B．wait for the boy to come

C．want to be left alone                     D．seek safety from any hurt

2.From the story, we can learn that ______.

A．the girl suffered a lot in her life

B．the girl’s parents divorced because of her

C．teachers and friends treated the girl badly

D．the girl used to stay in the tree when feeling sad

3.The underlined word “it” in the story refers to ______.

A．leaning back against the branch            B．being alone in the world

C．not being disturbed at night               D．it being dark with snow around

4.From the end of the story, it can be known that the girl _______.

A．knew the person                        B．knew what the object was

C．realized her wishes                      D．would never feel alone any more

Having said goodbye to his parents, Alvin, with his wife and one-year-old son, set off back home．  16 excited, Alvin and Clare talked and laughed happily． And even little Alax  17  from time to time． The family were   18  from trip．

   But about three hours later things began to   19  ． It was starting to snow． Alvin sped up the car,   20 to arrive home before dark． But it was too dangerous to drive fast now． Because it was snowing more and more heavily． So Alvin had to   21 down． The snow on the   22 was getting deeper and deeper until it was hard to   23 on it． Their car slipped (滑落) off the way and got stuck in the deep snow   24 the engine refused to start again．

“The snow doesn’t seem to   25  ． Shall we stay in the car waiting to be frozen to death or walk ahead through the snow?” Alvin asked． Clare said she  26  to walk． So they got out of the car with their son and began walking． But   27  was to come． Soon they lost their  28  and had to walk aimlessly on and on．

Night came． They were not afraid of the dark． But they were  29  that poor Alax would die of cold． However, their faith to keep Alax   30 made them filled with courage, warmth and strength． They  31 and rested in turn and then continued their walk． They had countless falls but each time true love encouraged them to rise to their   32  again．

One, two, three, …seven days passed． On the eighth day,   33  at last came from Alvin’s parents, the police and local people． But the young   34  had to have their feet cut off because of the bad frost-bites(冻伤)． Fortunately, there was  35  seriously wrong with little Alax．

1.A．Still             B．Even             C．Yet          D．Ever

2.A．cried       B．jumped           C．smiled       D．sang

3.A．taking      B．having            C．enjoying            D．starting

4.A．work   B．change           C．come        D．finish

5.A．phoning          B．deciding          C．thinking        D．hoping

6.A．get             B．slow               C．go           D．look

7.A．land            B．highway            C．fields        D．car

8.A．walk           B．sit                C．stay         D．wait

9.A．and             B．but              C．or             D．for

10.A．fall            B．end            C．continue      D．melt

11.A．liked          B．preferred         C．decided           D．wished

12.A．better        B．something       C．nothing            D．worse

13.A．hope           B．luck             C．way            D．money

14.A．certain       B．afraid           C．sorry          D．sure

15.A．happy       B．silent            C．alive            D．dead

16.A．slept           B．walked          C．watched        D．ate

17.A．heads       B．eyes             C．hands             D．feet

18.A．danger        B．help             C．luck            D．news

19.A．husband     B．wife         C．couple            D．baby

20.A．everything    B．anything        C．something    D．nothing

Against the assumption 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 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 have suggested that fire in northern regions speed up climate warming because greenhouse gases from burning trees and plants are released into the atmosphere and thus trap 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 ash from the fire fell on far-off 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 tracked the change in 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 predicated, 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.

According to the new findings, taking steps to prevent northern forest fires may _______.

   A. result in a warming climate      

B. cause the forest fires to occur more frequently

   C. lead to a longer fire season                      

D. protect the forests and the environment there

Earlier studies about northern forest fires ________.

   A. analyze all aspects of how northern fires influence climate

   B. indicate that forest fires will pollute the atmosphere

   C. suggest that people should take measures to protect environment

   D. suggest that the fires will speed up climate warming

The underlined phrase “soaked up” in the last paragraph most probably means ________.

       A. released        B. absorbed          C. created              D. disturbed

From the text we can draw a conclusion that forest fires in Alaska, Canada and Siberia may ______.

       A. warm the climate as the assumption goes

       B. allow more snow to reflect more sunlight into space and thus cool the climate

       C. destroy large areas of forests and pollute the far-off sea ice

       D. help to gain more energy rather than release more energy .

It is every citizen’s duty to go out to ______ the snow on the street______ it stops falling so as to make it convenient for traffic to pass. .