Many people believe the glare from snow causes snow blindness.Yet, with dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snowblindness, when exposed to several hours of "snow light". The United States Army has
题目
Many people believe the glare from snow causes snow blindness.Yet, with dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snowblindness, when exposed to several hours of "snow light". The United States Army has now determined that the glare from snow does not cause snow-blindness in troops in a snow-covered country.Rather, a mans eyes frequently find nothing to focus on in a broad expanse of a snow-covered area.So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at.Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscle aches.Nature balances this annoyance by producing more and more liquid which covers the eyeballs.The liquid covers the eyeballs in increasing quantity until vision blurs.And the result is total,even though temporary,snowblindness. Experiments led the Army to a simple method of overcoming this problem.Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape.Even the scouts themselves throw lightweight, dark-colored objects ahead on which they too can focus. The men following can then see something.Their gaze is arrested.Their eyes focus on a bush and having found something to see, stop searching through the snow- blanketed landscape.By focusing their attention on one object at a time, the man can cross the snow withoutbecoming hopelessly snowblind or lost.In this way the problem of crossing a solid white area is overcome.
The eyeballs become sore and the eye muscles ache because______.
A．tears cover the eyeballs
B．the eyes are annoyed by blinding sunlight
C．the eyes are annoyed by blinding snow
D．there is nothing to focus on
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第1题：
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．
The United States Army has now determined that glare from snow does not cause snow-
blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result is
total, even though temporary, snow-blindness．
Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．
?The scouts shake snow from evergreen bushes in order to__________ ．A.give the men behind something to see
B.beautify the landscape
C.warm themselves in the cold
D.prevent the men behind from losing their way答案：A解析：根据第三段“The men following can then see something．I'Ileir gaze is arrested”可知．侦查员摇落树上的雪是为了使后面的部队有物体可以聚焦，从而避免雪盲症的发生，故选A。 -
第2题：
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．
The United States Army has now determined that glare from snow does not cause snow-
blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result is
total, even though temporary, snow-blindness．
Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．
To prevent headaches, watering eyes and blindness caused by the glare from snow, dark glasses are__________ ．A.indispensible
B.useful
C.ineffective
D.available答案：C解析：根据第一段“Yet，dark glasses or not，theY find themselves suffering from headaches and watering eyes，and even snow—blindness”可知，深色眼镜并不起作用，故选C。 -
第3题：
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．
The United States Army has now determined that glare from snow does not cause snow-
blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result is
total, even though temporary, snow-blindness．
Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．
A suitable title for this passage would be __________ ．A.Snow-Blindness and How to Overcome It
B.Nature's Cure for Snow Blindness
C.Soldiers in the Snow
D.Snow Vision答案：A解析：本题考查全文主旨。全文讲的就是雪盲症怎么发生、怎么应对，故选A。 -
第4题：
There are many stereotypes about the character of people in various parts of the United States．In the Northeast and Midwest,people are said to be closed and private．In the South and West,however,they are often thought of as being more open and hospitable．Ask someone from St．Louis where the nearest sandwich shop is,and he or she will politely give you directions．A New Yorker might eye you at first and after deciding it is safe to talk to you,might give you a rather unexpected explanation．A person from Georgia might be very kind about directing you and even suggest some different places to eat．A Texan just might take you to the place and treat you to lunch.
American stereotypes are abundant．New Englanders are often thought of as being friendly and helpful．Southerners are known for their hospitality and warmth．People from the western part of the United States are often considered very outgoing．These differences in character can be traced to different factors such as climate,living conditions,and historical development.
When travelling from place to place,Americans themselves are often surprised at the differing degrees of friendliness in the United States.
The main idea of the passage is__.A.even Americans are surprised at the big differences among themselves
B.there are many differences in character in different parts of the USA
C.there are many reason for the differences
D.stereotypes about people are not necessarily true答案：B解析：第一个句子中写道“many stereotypes”，即可知应选B项。 -
第5题：
资料：When we see well，we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.
People who are near-sighted can only see things that are very close to their eyes，Everything else seems blurry（=unclear）.Many people who do a lot of work，such as writing，reading and sewing become near-sighted.
People who are far-sighted suffer from just the opposite problem. They can see things that are far away，but they have difficulty in reading a book unless they hold it at arm’s length. If they want to do much reading，they must get glasses，too.
Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism. This，too，can be corrected by glasses. Some people’s eyes become cloudy because of cataracts. Long ago these people often became blind. Now，however，it is possible to operate on the cataracts and remove them.
Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself，look at an object out of one eye；Then look at the same object out of your other eye. You will find the object’s relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distance as people with two eyes.
When things far away seem indistinct， one is probably______.A.astigmatic
B.far-sighted
C.suffering from cataracts
D.near-sighted答案：D解析：本题考查的是细节理解。
【关键词】things far away；indistinct
【主题句】第2自然段People who are near-sighted can only see things that are very close to their eyes，Everything else seems blurry（=unclear）. 近视的人只能看到非常接近他们眼睛的东西，其他一切看起来都很模糊（=不清楚）。
【解析】本题的问题是“当远处的东西看起来模糊不清时，可能就是？”A选项“散光”；B选项“远视”；C选项“患有白内障”；D选项“近视”。根据主题句，看不清远方的东西，应当是患有近视，故D选项正确。 -
第6题：
共用题干
Where Did the Earth's Water Come From?
Earth is located within the"snow line"of the solar system,the region closest to the Sun where H2 0 is primarily in liquid or gaseous form,if at all.______(46)The snow line phenomena is reflected in the water content of planets like Mercury,Venus,and Mars. Water is absent on Mercury.On Venus,H2O only exists as a trace element in the atmosphere.Mars only has a thin veneer of ice in its polar regions.In general,water is rare within the snow line.
Why does Earth have so much water relative to the other inner planets?71%of the surface is covered in the oceans,more than half of which is deeper than 3,000 meters,with an approximate total volume of 1.3 billion cu km.______(47)
There are various theories as to where all the Earth's water came from,but several theories have fared better than the others.______(48)When the Earth was in the process of forming,with a radius just 40%smaller than at present,it would have had enough gravity to hold on to a tenuous atmosphere with water vapor. The first water vapor on the planet would have come from the planet's internals,where volatile(low weight)chemicals would have a tendency to float to the top,and heavy chemicals(iron and nickel)would sink.
Though the first of Earth's water came about through volcanism,this alone probably didn't produce enough to form stable pools on the surface.______(49)Comparing the isotope ratios of water on Earth and water from comets and asteroids has revealed that the majority of the Earth's water comes from asteroids.
Throughout its history,Earth's water has increased in volume due to biological processes. In the early seas of Earth,hydrogen sulfide would have been in great supply,which,when reacted with carbon dioxide from the atmosphere during photosynthesis in sulfide-reducing bacteria,would have produced hydrogen,sulfur,and water.______(50)________（49）
A: More water was added to the planet during several hypothesized large impacts from asteroids from the outer asteroid belt.
B:We know that the oceans existed as early as 100 million years after the formation of the Earth.
C:Still,the oceans only make up 0.023%of the Earth's total mass.
D:Astronomers say Earth s water may have come from space.
E:The snow line is located in the outerasteroid belt,between the orbits of Mars and Jupiter.
F: Many geologists believe that the majority of Earth's water generated through this process.答案：A解析：文中第一段第一句提到了snow line，接下来的依据肯定还是要对snow line进行进一步说明，而选项中，只有E选项提到了snow line，所以选择E。
文中第二段主要说明地球上的水占的比重，而只有C选项是对这一主题进行说明，所以选择C。
根据后一句When the Earth was in the process of forming可以得知，该段是在讲述地球的形成历史，B选项We know that the oceans existed as early as 100 million years after the formation of the Earth也是在讲述地球形成的历史，所以选择B。
后一句：Comparing the isotope ratios of water on Earth and water from comets and asteroids has revealed that the majority of the Earth's water comes from asteroids．通过把地球上水的同位素和小行星以及彗星上的水的同位素进行比较，发现地球上的水主要来自小行星。可以推断出，该句要讲述地球上的水与太空中小行星的关系，所以A选项正确。
文中的最后一段主要是讲地球上水的来源。前一句：In the early seas of Earth,hydrogen sulfide would have been in great supply,which,when reacted with carbon dioxide from the atmosphere during photosynthesis in sulfide-reducing bacteria,would have produced hydrogen , sulfur , and water．在地球早期的海洋中，硫氢化合物非常丰富，在去硫细菌的光合作用的影响下，它与大气层中的二氧化碳产生化学反应，产生大量的氢、硫，以及水。这是地球自身产生的水，而F选项Many geologists believe that the majority of Earth's water generated through this process(许多地理学家认为地球上水的产生主要通过这一进程实现）正好承接前一句，所以F选项正确。 -
第7题：
Questions 21 to 25 are based on the following passage. 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 (北极的) 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 (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. 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
正确答案:A -
第8题：
Questions 21 to 25 are based on the following passage. 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 (北极的) 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 (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. 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
正确答案:D -
第9题：
Questions 21 to 25 are based on the following passage. 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 (北极的) 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 (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. 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
正确答案:B -
第10题：
单选题After the heavy snow storm many people _____ on the icy streets and injured their arms and legs.Aslipped
Bskipped
Cskied
Dtripped
正确答案： A解析：
句意：在大雪过后，许多人都在结冰的街道上滑倒，弄伤了手臂和腿。slip滑倒，跌跤。ski跳跃；跳读；遗漏。ski滑雪。trip绊倒，摔倒。 -
第11题：
单选题Passage1 Questions 1 to 5 are based on the following passage. It's interesting that the arrival of snow has the effect on people in different countries.(76) For some countries it is an important happening to celebrate each year, while for others a catastrophe （灾害） or even a wonder. But there are countries between these two kinds that normally expect snow some time over the winter months, but never receive snow regularly or in the same quantities every year.Britain is one of them, for which the arrival of snow quite simply creates problems.Within hours of the first snowfalls, however light, roads are blocked; trains and buses have to stop in the middle of the way.Normal communications are affected as well: telephone calls become difficult and the post immediately takes more time than usual.And almost within hours there are also certain shortages-bread, vegetables and other things-not because all these things can no longer be produced or sent to shops,but mainly because people are frightened and go out and store up with food and so on...just for fear that something bad should happen. But why does snow have this effect? After all, the Swiss, the Austrians and the Canadians don't have such problems.It is simply because there is not enough planning and preparation.We need money to buy equipment to deal with snow and ice.To keep the roads clear, for example,requires snow-ploughs (扫雪机) and machines to spread salt.(77) The reason why a country like Britain does not buy snow-ploughs is that they are only used for a few days in any one year, and the money could be more useful in other things such as hospitals, education, helping the old, and so on.3 After a few hours' snowing there are often some shortages of food because______.Ashops have closed down
Bpeople buy as much as they can
Cfarmers can produce no more
Dpeople eat more vegetables
正确答案： B解析： -
第12题：
单选题According to the writer, Britain is a country______.Awhich has regular snow
Bwhich is not well prepared for snow
Cfor which snow is a catastrophe
Dfor which snow is a wonder
正确答案： D解析： -
第13题：
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．
The United States Army has now determined that glare from snow does not cause snow-
blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result is
total, even though temporary, snow-blindness．
Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．
Snow-blindness may be avoided by__________A.concentrating to the solid white terrain
B.searching for something to look at in snow-covered terrain
C.providing the eyes with something to focus on
D.covering the eyeballs with fluid答案：C解析：根据第二段可知，雪盲症的发生最根本的原因是茫茫雪原上看不到除了白色以外的颜色，因而眼睛疲劳，因此提供可以聚焦的物体是根本预防办法，故选C。 -
第14题：
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．
The United States Army has now determined that glare from snow does not cause snow-
blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result is
total, even though temporary, snow-blindness．
Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．
?When the eyes are sore tears are produced toA.clear the vision
B.remedy snow-blindness
C.ease the irritation
D.loosen the muscles答案：C解析：根据第二段“the eyebaHs become sore…Nature offsets this irritation by producing more and fluid which covers the eyebaH”可知，眼泪的分泌是为了缓和刺激．故选C。 -
第15题：
Many people believe the glare from snow causes snow-blindness. Yet, dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light".
The United States Army has now determined that glare from snow does not cause snow- blindness in troops in a snow-covered country. Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscles ache. Nature offsets this irritation by producing more and fluid which covers the eyeball. The fluid
covers the eyeball in increasing quantity until vision blurs,then is observed, and the result is total, even though temporary, snow-blindness.
Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape. By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost. In this way the problem of crossing a solid white terrain is overcome.
To prevent headaches, watering eyes and blindness caused by the glare from snow, dark glasses are__________.A. indispensible
B. useful
C. ineffective
D. available答案：C解析：根据第一段“Yet，dark glasses or not，they find themselves suffering from headaches and
watering eyes。and even snow-blindness”可知，深色眼镜并不起作用，故选C。 -
第16题：
There are many stereotypes about the character of people in various parts of the United States．In the Northeast and Midwest,people are said to be closed and private．In the South and West,however,they are often thought of as being more open and hospitable．Ask someone from St．Louis where the nearest sandwich shop is,and he or she will politely give you directions．A New Yorker might eye you at first and after deciding it is safe to talk to you,might give you a rather unexpected explanation．A person from Georgia might be very kind about directing you and even suggest some different places to eat．A Texan just might take you to the place and treat you to lunch.
American stereotypes are abundant．New Englanders are often thought of as being friendly and helpful．Southerners are known for their hospitality and warmth．People from the western part of the United States are often considered very outgoing．These differences in character can be traced to different factors such as climate,living conditions,and historical development.
When travelling from place to place,Americans themselves are often surprised at the differing degrees of friendliness in the United States.
Which of the following is true according to the passage?A.New Yorkers are usually open with stranger
B.People from the South are usually considered good host
C.The friendliest Americans travel from place to plac
D.Different parts have different customs and habit答案：B解析：第一段中是美国不同地区人物性格的对比，不难看出，本题中只有B项是真实的。 -
第17题：
资料：When we see well，we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.
People who are near-sighted can only see things that are very close to their eyes，Everything else seems blurry（=unclear）.Many people who do a lot of work，such as writing，reading and sewing become near-sighted.
People who are far-sighted suffer from just the opposite problem. They can see things that are far away，but they have difficulty in reading a book unless they hold it at arm’s length. If they want to do much reading，they must get glasses，too.
Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism. This，too，can be corrected by glasses. Some people’s eyes become cloudy because of cataracts. Long ago these people often became blind. Now，however，it is possible to operate on the cataracts and remove them.
Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself，look at an object out of one eye；Then look at the same object out of your other eye. You will find the object’s relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distance as people with two eyes.
We should take good care of our eyes______.A.even if we can see well
B.only when we cannot see perfectly
C.only when we realize how important our eyes are
D.only when we can see well答案：A解析：本题考查的是细节理解。
【关键词】take good care of；our eyes
【主题句】第1自然段When we see well，we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are. 当我们看东西很清楚的时候，我们不经常想到我们的眼睛。只有当我们无法完美地看到时，我们才意识到我们的眼睛多么重要。
【解析】本题的问题是“我们应该好好保护我们的眼睛________”A选项“即使我们能看得很清楚”；B选项“当我们无法完美地看到时”；C选项“只有当我们意识到我们的眼睛有多重要时”；D选项“只有在我们能够看得出来的时候”。根据主题句分析可知，我们无论何时都要保护好眼睛，不要在看不清的时候才意识到严重性，故A选项符合题意。 -
第18题：
共用题干
The Dangers of Secondhand Smoke
Most people know that cigarette smoking is harmful to their health.Scientific research shows that it
causes many kinds of diseases.In fact,many people who smoke get lung cancer. However,Edward Gilson
has lung cancer,and he has never smoked cigarettes.He lives with his wife Evelyn,who has smoked about
a pack of cigarettes a day throughout their marriage.________(46)
No one knows for sure why Mr. Gilson has lung cancer. Nevertheless,doctors believe that secondhand
smoke may cause lung cancer in people who do not smoke because nonsmokers often breathe in the smoke
from other people's cigarettes.________(47)The US Environmental Protection Agency reports that about
53,000 people die in the United States each year as a result of exposure to secondhand smoke.
The smoke that comes from a lit cigarette contains many different poisonous chemicals.In the past,
scientists did not think that these chemicals could harm a nonsmoker's health._________(48)They
discovered that even nonsmokers had unhealthy amounts of these toxic chemicals in their bodies.As a matter
of fact,almost all of us breathe tobacco smoke at times,whether we realize it or not. For example,we can
not avoid secondhand smoke in restaurants,hotels and other public places.Even though many public places
have nonsmoking areas,smoke flows in from the areas where smoking is permitted.
It is even harder for children to avoid secondhand smoke._________(49)Research shows that chil-
dren who are exposed to secondhand smoke are sick more often than children who live in homes where no one
smokes and that the children of smokers are more than twice as likely to develop lung cancer when they are
adults as are children of nonsmokers.The risk is even higher for children who live in homes where both
parents smoke.
People are becoming very aware of the dangers of secondhand smoke._________（50)__________（50）
A:Recently,though,scientists changed their opinion after they studied a large group of nonsmokers.
B:The Gilsons have been married for 35 years.
C:This smoke is called secondhand smoke.
D:However,secondhand smoke is dangerous to all people,old or young.
E:As a result,they have passed laws which prohibit people from smoking in many public places.
F: In the United States,nine million children under the age of five live in homes with at least one smoker.答案：E解析：前一句主要讲的是，Gilson先生与妻子Evelyn生活在一起，而Evelyn自他们结婚以来 一直是每天差不多抽一包烟。接下来显然应选表示他们结婚年限的句子。再者，只有B项提 到了Gilsons。
前一句提到，不吸烟者时常吸人吸烟者吸烟时呼出的烟，后面应跟这种烟的定义，故选C。
前一句讲的是过去科学家们对二手烟的看法，接下来的句子应表示他们改变了看法， 因为后面的句子表明他们所持的观点已与过去截然不同。
前一句提到儿童与二手烟，接下来的句子自然仍然与儿童有关。
前一句讲的是人们逐渐意识到二手烟的危害，因此接下来的句子应表示人们采取措 施，禁止在公共场所吸烟。第6部分：完形填空 -
第19题：
Questions 21 to 25 are based on the following passage. 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 (北极的) 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 (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. It can be inferred from the last paragraph that scientists （）
- A、are puzzled by the mystery of forest pollution
- B、feel relieved by the use of unleaded gasoline
- C、still consider lead pollution a problem
- D、lack sufficient means to combat lead pollution
正确答案:C -
第20题：
Questions 21 to 25 are based on the following passage. 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 (北极的) 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 (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute. 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.
正确答案:D -
第21题：
单选题According to the Weather Channel, there is a ______ of rain or even snow in the southwestern region of the United States.Apotential
Bspeculation
Cchance
Dplan
正确答案： C解析：
句意：根据气象频道的报道，美国西南部地区可能会有降雨甚至降雪。此处意外“下雨或下雪的可能性”，用chance。选择C。potential潜力，潜能。speculation思索；做投机买卖。 -
第22题：
单选题Snow _____ is a big problem in some areas after the snow storm which lasts several days.Amobilization
Bpromotion
Cmotive
Dremoval
正确答案： B解析：
句意：在一些地区，持续数天的暴风雪后的积雪清扫工作是个大问题。removal排除，清除。mobilization动员。promotion促进；晋升。motive动机，目的。 -
第23题：
单选题The wordstwo kinds in Line 4 mean the countries______.Awhich have snow either as yearly happening to celebrate or as rare weather
Bwhich either have heavy snow or light snow
Cto which snow either causes problems or no problems
Dwhich either have snow-ploughs or no snow-ploughs
正确答案： D解析：