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单选题
—The water changes into thick ice covering rivers and lakes in winter in Harbin.—_____ in Urumqi and children go skating on it then.
A
So is it
B
So it does
C
So it is
D
So does it
参考答案
参考解析
解析：
由动词changes可判断，空格处应用助动词does，故排除A、C。当so提前到句首，且前后两句的主语不同时，句子用部分倒装，故选D。
由动词changes可判断，空格处应用助动词does，故排除A、C。当so提前到句首，且前后两句的主语不同时，句子用部分倒装，故选D。
更多 “单选题—The water changes into thick ice covering rivers and lakes in winter in Harbin.—_____ in Urumqi and children go skating on it then.A So is itB So it doesC So it isD So does it” 相关考题
考题
What keeps Grimsvotn still?A. The slow flow of waterB. The low water temperatureC. The thick glacierD. The water pressure
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First ,they polluted the rivers and lakes .Then they spend billions trying to control the pollution .This doesn’t make sense .It is absolutely stupid.()
此题为判断题(对，错)。
考题
Passage FiveFrom the beginning rivers have played an important part in the life of man. Man of the earliest times used the rivers as a means of traveling. Today rivers still serve as a great waterway for the transport and people.In ancient times, man settled near rivers or on river banks and built up large empires.Water is the Nature's most precious gift to man. Man needs water to irrigate his crops, to cook and to wash. In nations all over the world rivers mean life and wealth. They feed and clothe the nations around them.Water is also a source of energy and power. Man constructs huge dams across the river to control the water for irrigation and get the energy needed to drive generators. The electrical power is then directed to homes, cities, factories and television stations.Man uses water each day. His main source of water comes from reservoirs, which in turn get their water from the rivers.Rivers also bring down soil and minerals from the mountains and deposit them on the plains building up rich river deltas for raising plants and crops. Fresh water life in rivers or in lakes fed by them provide man with food.In a small way rivers help to keep man in good health and provide for his amusements. Various forms of water sports keep man strong and healthy.Rivers have run on this earth long before man. Man's future ability to live is uncertain, but rivers will flow on forever.52. Rivers have been important to man______.A. since the last centuryB. for a very long timeC. since a few hundred years agoD. since a few years ago
考题
As the ocean water changes to ice, it keeps the temperature______ falling too far.A、withB、intoC、besidesD、from
考题
请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.
The purpose of mentioning the Weddell Sea is__________.
查看材料
A．to give an example of cold-water salinity
B．to point out the location of deep waters
C．to make a comparison between hot-water salinity and cold-water salinity
D．to show that the water in the Weddell Sea varies in salinity from place to place
考题
请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.
Which of the following is not the cause of the decrease in the oceanic salinity?
查看材料A．Precipitation.
B．Rain and snow.
C．Formation of ice.
D．Addition of water by rivers.
考题
请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.
It can be known from the passage that increase in the salinity of ocean water is caused by__________.
查看材料A．melting of sea ice
B．precipitation
C．evaporation
D．supplement of salt
考题
请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.
Which of the following statements is TRUE according to the passage?
查看材料
A．Oceanic salinity has great effect on sea life.
B．Many factors combine to cause changes in oceanic salinity.
C．The movement of the water is related to the amount of salt.
D．The temperature of the water has much to do with the oceanic salinity.
考题
请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.
This passage mainly tells us about__________.
查看材料A．the analysis of the salinity of ocean waters
B．the causes of the variation in oceanic salinity
C．the importance of the changes in oceanic salinity
D．the different forms of salts in ocean waters
考题
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第三篇Preserve the EnvironmentThroughout history man has changed his physical environment in order to improve his way of life.With the tools of technology he has altered many physical features of the earth.He has transformed woodlands into farmland,and made lakes and reservoirs out of rivers for irrigation purposes or hydroelectric power. Man has also modified the face of the earth by draining marshes and cutting through mountains tobuild roads and railways.However,man's changes to the physical environment have not always had beneficial results.Today, pollution of the air and water is an increasing danger to the health of the planet.Each day thousands of tons of gases come out of the exhausts of motor vehicles;smoke from factories pollutes the air of industrialized areas and the surrounding areas of countryside.The air in cities is becoming increasingly unhealthy.The pollution of water is equally harmful.In the sea,pollution from oil is increasing and is killing enor- mous numbers of algae（水藻）,fish and birds.The whole ecological balance of the sea is being changed. The same problem exists in rivers.Industrial wastes have already made many rivers lifeless.Conservationists believe that it is now necessary for man to limit the growth of technology in order to sur-vive on earth.Who would most probably disagree with conservationists?A:Industrialists.B:Ecologists.C:Businessmen.D:Environmentalists.
考题
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第三篇Preserve the EnvironmentThroughout history man has changed his physical environment in order to improve his way of life.With the tools of technology he has altered many physical features of the earth.He has transformed woodlands into farmland,and made lakes and reservoirs out of rivers for irrigation purposes or hydroelectric power. Man has also modified the face of the earth by draining marshes and cutting through mountains tobuild roads and railways.However,man's changes to the physical environment have not always had beneficial results.Today, pollution of the air and water is an increasing danger to the health of the planet.Each day thousands of tons of gases come out of the exhausts of motor vehicles;smoke from factories pollutes the air of industrialized areas and the surrounding areas of countryside.The air in cities is becoming increasingly unhealthy.The pollution of water is equally harmful.In the sea,pollution from oil is increasing and is killing enor- mous numbers of algae（水藻）,fish and birds.The whole ecological balance of the sea is being changed. The same problem exists in rivers.Industrial wastes have already made many rivers lifeless.Conservationists believe that it is now necessary for man to limit the growth of technology in order to sur-vive on earth.According to the passage,pollution of the air and water is caused by__________.A:thousands of tons of gases coming out of the exhausts of motor vehiclesB:the changes of the environment that technology has brought to manC:the increasing amount of oil that has been producedD:industrial wastes discharged into rivers
考题
The ice is not thick enough to bear the weight of a tank.A:suffer B:accept C:receive D:support
考题
When the glaciers（ ）after the last ice age,the five Great Lakes of North America were formed.A.advanced
B.evaporated
C.thawed
D.exploded
考题
根据下列内容，回答201-205题。
When we analyze the salt salinity(盐浓度) of ocean waters, we find that it varies only slightlyfrom place to place. Nevertheless, some of these small changes are important. There are three basicprocesses that cause a change in oceanic salinity. One of these is the subtraction of water from theocean by means of evaporation. In this manner, the salinity is increased, since the salt stays be-hind. If this is carried to the extreme, of course, white salt would be left behind; this, by the
way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to theocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas ofhigh rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increasedby the subtraction of water by evaporation, or decreased by the addition of fresh water by precipi-tation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higherthan it is in other parts of the world where there is not as much evaporation. Similarly, in coastalregions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting ofsea ice. When seawater is frozen, the dissolved materials are left behind. In thismanner, seawaterdirectly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared.
Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing pro-cess, which increases the salinity of cold water. This heavy water sinks and is found in the deeperportion of the oceans of the world.
This passage mainly tells us about___________.A.the analysis of the salinity of ocean waters
B.the causes of the variation in oceanic salinity
C.the importance of the changes in oceanic salinity
D.the different forms of salts in ocean waters
考题
共用题干
WaterEarth is like a big blue marble.From high above the Earth and from the moon,the planet gleams and shines.The blue water in the oceans and seas of the Earth makes a dramatic image.The white clouds above the Earth add beauty to the picture.Water is the source of this beauty and the source of life on Earth.It is the reason people can live on this planet. Water is everywhere.(46)_______.It is in the soil,the ground that grows the food.Water is in rock deep under the ground, in natural holding areas一in storage.In a real sense,water keeps Earth alive.Nature has an unchanging amount of water. Nature has a perfect system for recycling water. (47)_____.It falls as rain.Then it goes to one of three places.It might sink slowly through the soil into the natural holding areas in the rock.(48)_______一by becoming vapor,or gas.It might run off into streams,rivers and oceans.By itself,nature can keep the balance and provide plenty of clean water for us.Nature recycles water.However,people cause problems for this natural recycling system.Nature's recycling system can work well(49)________.Some ways that people upset nature are easy to understand.For example, dirty sewage（污水沟系统）water from homes and factories must not mix with drinking water. People get sick from drinking contaminated water. Sometimes water from factories goes into streams and rivers.It enters into the groundwater. It can flow into lakes too.This kind of contamination from industry(waste water from factories) can be dangerous for people.If water contains poisons and chemicals,it is poison.(50)________;some poisons kill people as well as birds and animals.Without knowing,people can upset nature's recycling system.Lakes and rivers add beauty to the world. People enjoy water for entertainment purposes,too. People enjoy swimming and playing in the cool water of a lake in the summer. They like to ride on boats on rivers.Many people enjoy catching fish in the rivers.They fish for food and for sport.However,in some places,the water of the lakes and rivers is no longer safe.These rivers and lakes are contaminated.The fish are dying because of the chemicals from farms and factories.People cannot swim in the polluted water._________（49）A:Poison makes people sickB:It is in the air that people breatheC:We can not live without waterD:Water is used again and againE:only if people work with the system and not against it F: It might disappear into the air quickly
考题
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Europa's Watery UnderworldEuropa,one of Jupiter's 63 known moons,looks bright and icy on the surface.But appearances can be deceiving:Miles within its cracked,frigid shell,Europa probably hides giant pools of liquid water. Where scientists find liquid water,they hope to find life as well.Since we can't go diving into Europa's depths just yet,scientists instead have to investigate the moon's surface for clues to what lies beneath.In a new study,scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U.S.Great Lakes.Pictures of Europa,which is slightly smaller than Earth's moon,clearly show a tangled,icy mishmash of lines and cracks known as"chaos terrains".These chaotic places cover more than half of Europa. For more than 10 years,scientists have wondered what causes the formations.The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface.For scientists who suspect that Europa also may be hiding life beneath its icy surface,the news about the new lake is exciting."It would be great if these lakes harbored life,"Britney Schmidt,a planetary scientist who worked onthe study,told Science News."But even if they didn't,they say that Europa is doing something interesting and active right now."Schmidt,a scientist at the University of Texas at Austin,and her colleagues wanted to know how chaos terrains form.Since they couldn't rocket to Europa to see for themselves,they searched for similar forma- tions here on Earth.They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice.The scientists now suspect something similar might be happening on Europa:that as water and ice of different temperatures mingle and shift,the surface fractures.This would explain the jumbled ice sculptures."Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth,"Schmidt told Science News.She and her team found that the process could be causing chaos terrains to form quickly on Europa.The new study suggests that on this moon,elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life.The liquid water of an underground pool of Europa is estimated as much as the volume of the U.S.Great Lakes.A:RightB:WrongC:Not mentioned
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Europa's Watery UnderworldEuropa,one of Jupiter's 63 known moons,looks bright and icy on the surface.But appearances can be deceiving:Miles within its cracked,frigid shell,Europa probably hides giant pools of liquid water. Where scientists find liquid water,they hope to find life as well.Since we can't go diving into Europa's depths just yet,scientists instead have to investigate the moon's surface for clues to what lies beneath.In a new study,scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U.S.Great Lakes.Pictures of Europa,which is slightly smaller than Earth's moon,clearly show a tangled,icy mishmash of lines and cracks known as"chaos terrains".These chaotic places cover more than half of Europa. For more than 10 years,scientists have wondered what causes the formations.The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface.For scientists who suspect that Europa also may be hiding life beneath its icy surface,the news about the new lake is exciting."It would be great if these lakes harbored life,"Britney Schmidt,a planetary scientist who worked onthe study,told Science News."But even if they didn't,they say that Europa is doing something interesting and active right now."Schmidt,a scientist at the University of Texas at Austin,and her colleagues wanted to know how chaos terrains form.Since they couldn't rocket to Europa to see for themselves,they searched for similar forma- tions here on Earth.They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice.The scientists now suspect something similar might be happening on Europa:that as water and ice of different temperatures mingle and shift,the surface fractures.This would explain the jumbled ice sculptures."Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth,"Schmidt told Science News.She and her team found that the process could be causing chaos terrains to form quickly on Europa.The new study suggests that on this moon,elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life.The strange ice patterns on Europa are formed as a result of a mixture of liquid water and solid material underground water pool.A:RightB:WrongC:Not mentioned
考题
共用题干
Europa's Watery UnderworldEuropa,one of Jupiter's 63 known moons,looks bright and icy on the surface.But appearances can be deceiving:Miles within its cracked,frigid shell,Europa probably hides giant pools of liquid water. Where scientists find liquid water,they hope to find life as well.Since we can't go diving into Europa's depths just yet,scientists instead have to investigate the moon's surface for clues to what lies beneath.In a new study,scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U.S.Great Lakes.Pictures of Europa,which is slightly smaller than Earth's moon,clearly show a tangled,icy mishmash of lines and cracks known as"chaos terrains".These chaotic places cover more than half of Europa. For more than 10 years,scientists have wondered what causes the formations.The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface.For scientists who suspect that Europa also may be hiding life beneath its icy surface,the news about the new lake is exciting."It would be great if these lakes harbored life,"Britney Schmidt,a planetary scientist who worked onthe study,told Science News."But even if they didn't,they say that Europa is doing something interesting and active right now."Schmidt,a scientist at the University of Texas at Austin,and her colleagues wanted to know how chaos terrains form.Since they couldn't rocket to Europa to see for themselves,they searched for similar forma- tions here on Earth.They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice.The scientists now suspect something similar might be happening on Europa:that as water and ice of different temperatures mingle and shift,the surface fractures.This would explain the jumbled ice sculptures."Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth,"Schmidt told Science News.She and her team found that the process could be causing chaos terrains to form quickly on Europa.The new study suggests that on this moon,elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life.The existence of liquid water is a necessity for a life-support environment.A:RightB:WrongC:Not mentioned
考题
共用题干
第一篇Water Resources on the EarthThe second most important constituent（构成成分）of the biosphere（生物圈）is liquid water. This can only exist in a very narrow range of temperatures,since water freezes at 0℃and boils a 100℃．Life as we know it would only be possible on the surface of a planet which had temperature: somewhere within this narrow range.The earth's supply of water probably remains fairly constant in quantity.The total quantity of water is not known very accurately,but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers.Most of it is in the form of the salt water of the oceans一about 97 percent. The rest is fresh.But three-quarters of this is in the form of ice at the poles and or mountains and cannot be used by living systems until melted.Of the remaining fraction,which h somewhat less than one percent of the whole.There is 10—20 times as much stored underground water as there is actually on the surface.There is also a tiny,but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation（循环） of the biosphere has to pass.Water evaporated（蒸发）from the surface of the oceans,from lakes and rivers and from moist（潮湿的）earth is added to it. From it the water comes out again as rain or snow,falling on either the sea or the land. There is,as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land,but there is more rainfall over the land than over the oceans and the balance is restored by the run off from the land in the form of rivers.The word"fraction"in the second paragraph means________.A:a large areaB:a very small amountC:an important systemD:a major source of information
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第一篇Water Resources on the EarthThe second most important constituent（构成成分）of the biosphere（生物圈）is liquid water. This can only exist in a very narrow range of temperatures,since water freezes at 0℃and boils a 100℃．Life as we know it would only be possible on the surface of a planet which had temperature: somewhere within this narrow range.The earth's supply of water probably remains fairly constant in quantity.The total quantity of water is not known very accurately,but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers.Most of it is in the form of the salt water of the oceans一about 97 percent. The rest is fresh.But three-quarters of this is in the form of ice at the poles and or mountains and cannot be used by living systems until melted.Of the remaining fraction,which h somewhat less than one percent of the whole.There is 10—20 times as much stored underground water as there is actually on the surface.There is also a tiny,but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation（循环） of the biosphere has to pass.Water evaporated（蒸发）from the surface of the oceans,from lakes and rivers and from moist（潮湿的）earth is added to it. From it the water comes out again as rain or snow,falling on either the sea or the land. There is,as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land,but there is more rainfall over the land than over the oceans and the balance is restored by the run off from the land in the form of rivers.Most of the fresh water on Earth________.A:is in the form of ice at the poles and on mountainsB:is stored undergroundC:is found in rivers and lakesD:comes from the rain
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第一篇Water Resources on the EarthThe second most important constituent（构成成分）of the biosphere（生物圈）is liquid water. This can only exist in a very narrow range of temperatures,since water freezes at 0℃and boils a 100℃．Life as we know it would only be possible on the surface of a planet which had temperature: somewhere within this narrow range.The earth's supply of water probably remains fairly constant in quantity.The total quantity of water is not known very accurately,but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers.Most of it is in the form of the salt water of the oceans一about 97 percent. The rest is fresh.But three-quarters of this is in the form of ice at the poles and or mountains and cannot be used by living systems until melted.Of the remaining fraction,which h somewhat less than one percent of the whole.There is 10—20 times as much stored underground water as there is actually on the surface.There is also a tiny,but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation（循环） of the biosphere has to pass.Water evaporated（蒸发）from the surface of the oceans,from lakes and rivers and from moist（潮湿的）earth is added to it. From it the water comes out again as rain or snow,falling on either the sea or the land. There is,as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land,but there is more rainfall over the land than over the oceans and the balance is restored by the run off from the land in the form of rivers.Liquid water only exists________.A: in the center of the earthB:on the surface of our planetC:in the coastal areas of the earthD:in a very narrow range of temperatures
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第一篇Water Resources on the EarthThe second most important constituent（构成成分）of the biosphere（生物圈）is liquid water. This can only exist in a very narrow range of temperatures,since water freezes at 0℃and boils a 100℃．Life as we know it would only be possible on the surface of a planet which had temperature: somewhere within this narrow range.The earth's supply of water probably remains fairly constant in quantity.The total quantity of water is not known very accurately,but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers.Most of it is in the form of the salt water of the oceans一about 97 percent. The rest is fresh.But three-quarters of this is in the form of ice at the poles and or mountains and cannot be used by living systems until melted.Of the remaining fraction,which h somewhat less than one percent of the whole.There is 10—20 times as much stored underground water as there is actually on the surface.There is also a tiny,but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation（循环） of the biosphere has to pass.Water evaporated（蒸发）from the surface of the oceans,from lakes and rivers and from moist（潮湿的）earth is added to it. From it the water comes out again as rain or snow,falling on either the sea or the land. There is,as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land,but there is more rainfall over the land than over the oceans and the balance is restored by the run off from the land in the form of rivers.There is more of rainfall________.A:over the mountains than over the riversB:over the rivers than over the mountainsC:over the land than over the oceansD:over the oceans than over the land
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The ice is not thick enough to bear the weight of a tank.A:suffer B:accept C:receive D:support
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第一篇Arctic MeltEarth’s North and South Poles are famous for being cold and icy.Last year,however,the amnount of ice in the Arctic Ocean（北冰洋）fell to a record low.Normally,ice builds in Arctic waters around the North Pole each winter and shrinks（缩小）during the summer. But for many years,the amount of ice left by the end of summer has been declining.Since 1979,each decade has seen an 11.4 percent drop in end?of-summer ice cover. Between 1981 and 2000,ice in the Arctic lost 22 percent of its thickness,becoming I.13 meters thinner.Last summer,Arctic sea ice reached its thinnest levels yet.By the end of summer 2007,the ice had shrunk to cover just 4.2 million square kilometers.That's 38 percent less area than the average cover at that time of year. And it's a very large 23 percent below the previous record low,which was set just 2 years ago. This continuing trend has made scientists concerned.There may be several reasons for the ice melt, says Jinlun Zhang, an oceanographer（海洋学家）at the University of Washington at Seattle.Unusually strong winds blew through the Arctic last summer. The winds pushed much of the ice out of the central Arctic,leaving a large area of thin ice and open water.Scientists also suspect that fewer clouds cover the Arctic now than in the past.Clearer skies allow more sunlight to reach the ocean.The extra heat warms both the water and the atmosphere.In parts of the Arctic Ocean last year,surface temperatures were 3.5℃warmer than average and 1.5℃warmer than the previous record high.With both air and water getting warmer,the ice is melting from both above and below. In some parts of the Beaufort Sea,north of Alaska and western Canada,ice that measured 3.3 meters thick at the beginning of the summer measured just 50 centimeters by season's end.The new measurements suggest that melting is far more severe than scientists have seen by just looking at ice covcrfrom above,says Donald K. Perovich,a geophysicist at the U.S.Army Cold Regions Researchand Engineering Laboratory in Hanover,N.H.Some scientists fear that the Arctic is stuck in a warming trend from which it may never recover.The Beaufort Sea mentioned in Paragraph 7 is an example to show_________. A:how acetirate the new measurements areB:how thick the ice is in itC:how serious the problem of the ice melt in the Arctic isD:how dangerous it is to travel to it
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单选题As the ocean water changes to ice, it keeps the temperature（）falling too far.A
withB
intoC
besidesD
from
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单选题The author says that in some hot and dry areas it is advisable to _____.A
build big lakes to store waterB
construct big pumping stationsC
channel water from nearby rivers to croplandD
build small and cheap irrigation systems
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单选题Which of the following is the best way to revise sentences 13 and 14 (reproduced below) in the context of the passage?There are many recreations and nature attractions in this area, like golf courses, lakes, rivers, caverns, and mountains. People really don't know what the place has w offer.A
You might not realize that this area offer a range of natural attractions and recreations activities, including golf courses, lake, river, caverns, and mountains.B
People unfamiliar with Branson might not realize that this area offers a tango of natural attractions and recreational activities, including golf courses, lakes, rivers, caverns, and mountains.C
People might not realize that golf courses, lakes, river, caverns,, and mountains might all be found in Branson if they were to visitD
People unfamiliar with Brason do not that golf courses, lakes, river, caverns. mountains－can all be found in the Branson area if they were to visit.E
You might not realize, if unfamiliar with Branson, 'the range of natural and recreational resources available in the city, golf courses, lakes, rivers, caverns, and mountains being just a few.
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