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Man must stop ___ the earth’s atmosphere.
A.wasting
B.polluting
C.filling
D.emitting
参考答案
更多 “ Man must stop ___ the earth’s atmosphere. A.wastingB.pollutingC.fillingD.emitting ” 相关考题
考题
–Uncle John has cancer and it has spread throughout his body.–().
A、What a shock.B、It’s impossible.C、He is a good man.D、He must go to the hospital.
考题
8． You must be very tired ,why not ________a rest?A． to stop to haveB． to stop havingC． stop to haveD． stop having
考题
A()man will stop at nothing to get what he wants.
A、desirableB、desperateC、favorableD、reliable
考题
The topic of the passage is that __.A.the control of population is essential to the development of a nationB.natural resources are important to the economic development of a countryC.awareness of the effects of man's actions is as important as population controlD. developed countries should do more to protect natural environment on the earth
考题
29． Why are green plants and grass helpful?A． Because they can hold the water．B． Because they can stop the wind from blowing the earth away．C． Because they can keep the earth wet．D．All the above．
考题
The problem of underground water is more serious because（ ）[A] the underground water trickles away all the year round[B] the underground water is hidden deep beneath the Earth[C] the change of it must be controlled by the NASA's satellites[D] the dramatic change of it might affect the gravitational field
考题
Permanent magnetism is caused by ______.A.operation of electrical equipment and generators on board shipB.the earth's magnetic field affecting the ship's hard iron during constructionC.the horizontal component of the earth's magnetic field acting on the horizontal soft ironD.the vertical component of the earth's magnetic field acting on the vertical soft iron
考题
Passage 2
If the population of the earth goes on increasing at its present rate, there will eventually not be enough resources left to sustain life on the planet. By the middle of the 21st century, if present trends continue, we will have used up all the oil that drives our cars, for example. Even if scientists develop new ways of feeding the human race, the crowded conditions on earth will make it necessary for us to look for open space somewhere else. But none of the other planets in our solar system are capable of supporting life at present. One possible solution to the problem, however, has recently been suggested by an American scientist, Professor Carl Sagan.
Sagan believes that before the earth's resources are completely exhausted it will be possible to change the atmosphere of Venus and so create a new world almost as large as earth itself. The difficulty is that Venus is much hotter than the earth and there is only a tiny amount of water there.
Sagan proposes that algae organisms, which can live in extremely hot or cold atmospheres and at the same time produce oxygen, should be bred in conditions similar to those on Venus. As soon as this has been done, the algae will be placed in small rockets. Spaceships will then fly to Venus and fire the rockets into the atmosphere. In a fairly short time, the algae will break down the carbon dioxide into oxygen and carbon.
When the algae have done their work, the atmosphere will become cooler, but before man can set foot on Venus it will be necessary for the oxygen to produce rain. The surface of the planet will still be too hot for men to land on it but the rain will eventually fall and in a few years something like earth will be reproduced on Venus.
Man can eventually land on Venus only when__________.A. the algae have done their work
B. the atmosphere becomes cooler
C. there is oxygen
D. it rains there
考题
Passage 2
If the population of the earth goes on increasing at its present rate, there will eventually not be enough resources left to sustain life on the planet. By the middle of the 21st century, if present trends continue, we will have used up all the oil that drives our cars, for example. Even if scientists develop new ways of feeding the human race, the crowded conditions on earth will make it necessary for us to look for open space somewhere else. But none of the other planets in our solar system are capable of supporting life at present. One possible solution to the problem, however, has recently been suggested by an American scientist, Professor Carl Sagan.
Sagan believes that before the earth's resources are completely exhausted it will be possible to change the atmosphere of Venus and so create a new world almost as large as earth itself. The difficulty is that Venus is much hotter than the earth and there is only a tiny amount of water there.
Sagan proposes that algae organisms, which can live in extremely hot or cold atmospheres and at the same time produce oxygen, should be bred in conditions similar to those on Venus. As soon as this has been done, the algae will be placed in small rockets. Spaceships will then fly to Venus and fire the rockets into the atmosphere. In a fairly short time, the algae will break down the carbon dioxide into oxygen and carbon.
When the algae have done their work, the atmosphere will become cooler, but before man can set foot on Venus it will be necessary for the oxygen to produce rain. The surface of the planet will still be too hot for men to land on it but the rain will eventually fall and in a few years something like earth will be reproduced on Venus.
CarlSagan believes that Venus might be colonized from earth because__________.A. it might be possible to change its atmosphere
B. its atmosphere is the same as the earth's
C. there is a good supply of water on Venus
D. the days on Venus are long enough
考题
共用题干
The world has got rainforests which cover 7% of the earth's surface.They grow around the earth's equator in South America,Central America,Africa,Southeast Asia,and Australia. Rainforests are important.(46)______.These rainforests are wet and warm.They get more than two meters of rain each year,and temperatures are usually between 24℃and 27℃．(47)______. Each area has a different environment with different plants,trees and animals.(48)______.Every day a part of the rainforest,the same size as a football field,is destroyed because of human activities.(49)______,people cut down trees to make plantations to grow food,to get minerals or metals out of the ground or to build more and more houses.(50) ______.Cutting down trees must be prohibited and wild animals must be protected.If people break these rules,they must be arrested and severely punished._________（47）A:Therefore strict measures must be takenB:They give the earth oxygen,and are the home for half of the world's animals and plantsC:Because of a growing populationD:Unfortunately,these rainforests are in dangerE:Tropical rainforests are home to tribal peoples who rely on their surroundings for food,shelter,and medicinesF: They are divided into four different areas
考题
共用题干
To Survive or to Vanish1.Over 3.6 billion years ago,the first creature was born in the world.Since then,the earth started its era with life.The history of life on earth has been a history of interaction between living things and their surroundings.To a large extent,the physical form and the habits of the earth's vegetation and its animal life have been molded by the environment. Considering the whole span of earthly time,the opposite effect,in which life actually modifies its surroundings,has been relatively slight. Only in the present century has one species一man acquired significant power to alter the nature of his world.2.During the past 25 years,this power has not only become increasingly great but it has changed in character. The most alarming of all man's assaults upon the environment is the contamination of air,earth,rivers,and sea with dangerous and even lethal materials. This pollution is for the most part irrecoverable.In this now universal contamination of the environment,chemicals are the sinister partners of radiation in changing the very nature of the world the very nature of its life. Chemicals sprayed on croplands or forests or gardens lie long in soil,entering into living organisms, passing from one to another in a chain of poisoning and death.Or they pass mysteriously by underground streams until they emerge and combine into new forms that kill vegetation,sicken cattle,and work unknown harm on those who drink from once pure wells."Man can hardly even recognize the devils of his own creation,"as a scientist has said.3.Hundreds of millions of years have passed before the globe produced the life that now inhabits the earth.Given time not in years but in millennia life adjusts,and a balance has been reached.But in the modern world there is no time.4.The quick steps of change follows the impetuous pace of man rather than the deliberate pace of nature.Radiation is now the unnatural creation of man's tampering with the atom.The chemicals are the synthetic creations of man's inventive mind,having no counterparts in nature.5.To survive these chemicals would require not merely the years of one man's life but the life of generations.And even this,were it by some miracle possible,would be futile,for the new chemicals come from our laboratories in an endless stream;almost five hundred annually find their way into actual use in the United States alone.Among them are many that are used in man's war against nature.Since the mid l940's over 200 basic chemicals have been created for use in killing insects,weeds,and other organisms described as"pests".6.It is not my contention that chemical insecticides must never he used.I do contend that we have put poisonous and biologically potent chemicals indiscriminately into the hands of persons largely or wholly ignorant of their potentials for harm. We have subjected enormous numbers of people to contact with these poisons,without their consent and often without their knowledge.I contend,furthermore,that we have allowed these chemicals to be used with little or no advance investigation of their effect on soil,water,wildlife,and man himself. Future generations are unlikely to forgive our lack of concern for the integrity of the natural world that supports all life.Human's pollution on nature is for the most part_______.A:man's tampering with the atomB:enormous numbers of people to contact with these poisonsC:the integrity of the natural world that supports all lifeD:inventiveE:irrecoverableF:relatively slight
考题
共用题干
To Survive or to Vanish1.Over 3.6 billion years ago,the first creature was born in the world.Since then,the earth started its era with life.The history of life on earth has been a history of interaction between living things and their surroundings.To a large extent,the physical form and the habits of the earth's vegetation and its animal life have been molded by the environment. Considering the whole span of earthly time,the opposite effect,in which life actually modifies its surroundings,has been relatively slight. Only in the present century has one species一man acquired significant power to alter the nature of his world.2.During the past 25 years,this power has not only become increasingly great but it has changed in character. The most alarming of all man's assaults upon the environment is the contamination of air,earth,rivers,and sea with dangerous and even lethal materials. This pollution is for the most part irrecoverable.In this now universal contamination of the environment,chemicals are the sinister partners of radiation in changing the very nature of the world the very nature of its life. Chemicals sprayed on croplands or forests or gardens lie long in soil,entering into living organisms, passing from one to another in a chain of poisoning and death.Or they pass mysteriously by underground streams until they emerge and combine into new forms that kill vegetation,sicken cattle,and work unknown harm on those who drink from once pure wells."Man can hardly even recognize the devils of his own creation,"as a scientist has said.3.Hundreds of millions of years have passed before the globe produced the life that now inhabits the earth.Given time not in years but in millennia life adjusts,and a balance has been reached.But in the modern world there is no time.4.The quick steps of change follows the impetuous pace of man rather than the deliberate pace of nature.Radiation is now the unnatural creation of man's tampering with the atom.The chemicals are the synthetic creations of man's inventive mind,having no counterparts in nature.5.To survive these chemicals would require not merely the years of one man's life but the life of generations.And even this,were it by some miracle possible,would be futile,for the new chemicals come from our laboratories in an endless stream;almost five hundred annually find their way into actual use in the United States alone.Among them are many that are used in man's war against nature.Since the mid l940's over 200 basic chemicals have been created for use in killing insects,weeds,and other organisms described as"pests".6.It is not my contention that chemical insecticides must never he used.I do contend that we have put poisonous and biologically potent chemicals indiscriminately into the hands of persons largely or wholly ignorant of their potentials for harm. We have subjected enormous numbers of people to contact with these poisons,without their consent and often without their knowledge.I contend,furthermore,that we have allowed these chemicals to be used with little or no advance investigation of their effect on soil,water,wildlife,and man himself. Future generations are unlikely to forgive our lack of concern for the integrity of the natural world that supports all life.The effect of life modifying its surroundings has been_______.A:man's tampering with the atomB:enormous numbers of people to contact with these poisonsC:the integrity of the natural world that supports all lifeD:inventiveE:irrecoverableF:relatively slight
考题
共用题干
To Survive or to Vanish1.Over 3.6 billion years ago,the first creature was born in the world.Since then,the earth started its era with life.The history of life on earth has been a history of interaction between living things and their surroundings.To a large extent,the physical form and the habits of the earth's vegetation and its animal life have been molded by the environment. Considering the whole span of earthly time,the opposite effect,in which life actually modifies its surroundings,has been relatively slight. Only in the present century has one species一man acquired significant power to alter the nature of his world.2.During the past 25 years,this power has not only become increasingly great but it has changed in character. The most alarming of all man's assaults upon the environment is the contamination of air,earth,rivers,and sea with dangerous and even lethal materials. This pollution is for the most part irrecoverable.In this now universal contamination of the environment,chemicals are the sinister partners of radiation in changing the very nature of the world the very nature of its life. Chemicals sprayed on croplands or forests or gardens lie long in soil,entering into living organisms, passing from one to another in a chain of poisoning and death.Or they pass mysteriously by underground streams until they emerge and combine into new forms that kill vegetation,sicken cattle,and work unknown harm on those who drink from once pure wells."Man can hardly even recognize the devils of his own creation,"as a scientist has said.3.Hundreds of millions of years have passed before the globe produced the life that now inhabits the earth.Given time not in years but in millennia life adjusts,and a balance has been reached.But in the modern world there is no time.4.The quick steps of change follows the impetuous pace of man rather than the deliberate pace of nature.Radiation is now the unnatural creation of man's tampering with the atom.The chemicals are the synthetic creations of man's inventive mind,having no counterparts in nature.5.To survive these chemicals would require not merely the years of one man's life but the life of generations.And even this,were it by some miracle possible,would be futile,for the new chemicals come from our laboratories in an endless stream;almost five hundred annually find their way into actual use in the United States alone.Among them are many that are used in man's war against nature.Since the mid l940's over 200 basic chemicals have been created for use in killing insects,weeds,and other organisms described as"pests".6.It is not my contention that chemical insecticides must never he used.I do contend that we have put poisonous and biologically potent chemicals indiscriminately into the hands of persons largely or wholly ignorant of their potentials for harm. We have subjected enormous numbers of people to contact with these poisons,without their consent and often without their knowledge.I contend,furthermore,that we have allowed these chemicals to be used with little or no advance investigation of their effect on soil,water,wildlife,and man himself. Future generations are unlikely to forgive our lack of concern for the integrity of the natural world that supports all life.Paragraph 1_______A:Man should be cautious in chemical use.B:It takes generations for mankind to adapt themselves to the chemicals.C:Chemicals are human's inventionD:Human's power increases and has changed its character in the past quarter century.E:The new change in the relationship between earth and its creature一human's power playing a greater role in changing the worldF: Modern world gives no time for nature to adjust to human.
考题
Each man and woman must sign ______ full names before entering the examination room.A.his
B.her
C.their
D.one’s
考题
共用题干
Early Ideas about the Universe1 Early man got his ideas about the universe by looking at the stars as you do.He observed carefully,and learned many things about the sun,the moon,and the stars.2 Suppose you were asked to collect evidence about the sun as early man did.You might go out morning after morning and see it come up in the east.Even on cloudy mornings,youwould observe that the darkness goes away and the world becomes light.You might not see the sun but would be sure it is there,because you notice that the earth warms up.As you continued,the sun climbs higher in the sky each day during part of the year. It stays in the sky longer. The earth gets warmer. Things begin to grow. It is spring and then summer.3 After a while the sun stays in the sky for shorter and shorter periods.Many plants begin to die.Leaves fall.Winter comes.Year after year this is repeated and you cannot tell exactly why it happens.But you realize that the sun seems to make the difference. Primitive（原始的）man felt that since the sun was so powerful it must be a god. It may seem silly to us now to worship（崇拜）a sun-god, but primitive man was right about the importance of the sun to life on earth.4 You have been told that the world is round.But suppose no one had ever taught you that the world was like a huge ball.Would you have ever thought of it yourself?You cannot see the curve（曲线）of the earth at once. You would have no idea of how big it was. That's why early man believed that the earth was small and flat.Such ideas appeared from the evidence they had.5 If you watch the stars night after night,you will see them rise and set.As you look at the sky,it is not difficult to imagine that you are in the center of a vast collection of twinkling（闪烁）lights. Some early astronomers（天文学家）believed the sky was a crystal shell or series of crystal shells,one inside the other. They believed this because that is what the night sky looked like.For many centuries,men believed that the earth was the center of the universe and that the sun,the moon,and the stars circled around it.Early man thought the earth was small and flat because_________.A:he did not observe the sun carefully enoughB:he could not see its curveC:the sun,the moon and the stars seemed to move around itD:the earth circles around the sunE:it looked like that at nightF:it has power over life on earth
考题
共用题干
Early Ideas about the Universe1 Early man got his ideas about the universe by looking at the stars as you do.He observed carefully,and learned many things about the sun,the moon,and the stars.2 Suppose you were asked to collect evidence about the sun as early man did.You might go out morning after morning and see it come up in the east.Even on cloudy mornings,youwould observe that the darkness goes away and the world becomes light.You might not see the sun but would be sure it is there,because you notice that the earth warms up.As you continued,the sun climbs higher in the sky each day during part of the year. It stays in the sky longer. The earth gets warmer. Things begin to grow. It is spring and then summer.3 After a while the sun stays in the sky for shorter and shorter periods.Many plants begin to die.Leaves fall.Winter comes.Year after year this is repeated and you cannot tell exactly why it happens.But you realize that the sun seems to make the difference. Primitive（原始的）man felt that since the sun was so powerful it must be a god. It may seem silly to us now to worship（崇拜）a sun-god, but primitive man was right about the importance of the sun to life on earth.4 You have been told that the world is round.But suppose no one had ever taught you that the world was like a huge ball.Would you have ever thought of it yourself?You cannot see the curve（曲线）of the earth at once. You would have no idea of how big it was. That's why early man believed that the earth was small and flat.Such ideas appeared from the evidence they had.5 If you watch the stars night after night,you will see them rise and set.As you look at the sky,it is not difficult to imagine that you are in the center of a vast collection of twinkling（闪烁）lights. Some early astronomers（天文学家）believed the sky was a crystal shell or series of crystal shells,one inside the other. They believed this because that is what the night sky looked like.For many centuries,men believed that the earth was the center of the universe and that the sun,the moon,and the stars circled around it.Primitive man believed the sun was a god because_________.A:he did not observe the sun carefully enoughB:he could not see its curveC:the sun,the moon and the stars seemed to move around itD:the earth circles around the sunE:it looked like that at nightF:it has power over life on earth
考题
共用题干
Early Ideas about the Universe1 Early man got his ideas about the universe by looking at the stars as you do.He observed carefully,and learned many things about the sun,the moon,and the stars.2 Suppose you were asked to collect evidence about the sun as early man did.You might go out morning after morning and see it come up in the east.Even on cloudy mornings,youwould observe that the darkness goes away and the world becomes light.You might not see the sun but would be sure it is there,because you notice that the earth warms up.As you continued,the sun climbs higher in the sky each day during part of the year. It stays in the sky longer. The earth gets warmer. Things begin to grow. It is spring and then summer.3 After a while the sun stays in the sky for shorter and shorter periods.Many plants begin to die.Leaves fall.Winter comes.Year after year this is repeated and you cannot tell exactly why it happens.But you realize that the sun seems to make the difference. Primitive（原始的）man felt that since the sun was so powerful it must be a god. It may seem silly to us now to worship（崇拜）a sun-god, but primitive man was right about the importance of the sun to life on earth.4 You have been told that the world is round.But suppose no one had ever taught you that the world was like a huge ball.Would you have ever thought of it yourself?You cannot see the curve（曲线）of the earth at once. You would have no idea of how big it was. That's why early man believed that the earth was small and flat.Such ideas appeared from the evidence they had.5 If you watch the stars night after night,you will see them rise and set.As you look at the sky,it is not difficult to imagine that you are in the center of a vast collection of twinkling（闪烁）lights. Some early astronomers（天文学家）believed the sky was a crystal shell or series of crystal shells,one inside the other. They believed this because that is what the night sky looked like.For many centuries,men believed that the earth was the center of the universe and that the sun,the moon,and the stars circled around it.Early astronomers believed that the sky was a crystal shell or series of crystal shells because_________.A:he did not observe the sun carefully enoughB:he could not see its curveC:the sun,the moon and the stars seemed to move around itD:the earth circles around the sunE:it looked like that at nightF:it has power over life on earth
考题
单选题According to the passage, the Earth’s magnetic field has _____.A
begun to change in the opposite directionB
been weakening in strength for a long timeC
caused the changes on the polaritiesD
misguided many a man and animal
考题
单选题According to the experts, the reversal of the Earth’s magnetic field would _____.A
destroy almost all the creatures on the EarthB
cause some species extinctions on the EarthC
not be as disastrous as the previous oneD
cause no big trouble for man and animals
考题
单选题We can conclude from the last paragraph that______.A
trade winds are harmful to the low clouds.B
deep clouds are helpful to cool the earth.C
global warming can result in more low clouds.D
global warming can destroy the form of atmosphere.
考题
单选题According to the passage, _____.A
we should not worry about the transition of the Earth’s magnetic fieldB
the Earth’s magnetic field will not change for at least 2000 yearsC
the Earth’s magnetic field has decreased its strength rapidlyD
the transition of the Earth’s magnetic field can be controlled by modern science
考题
单选题If the earth suddenly ________spinning, people would all fly off it.A
had stoppedB
stoppedC
has stoppedD
would stop
考题
单选题Permanent magnetism is caused by（）.A
operation of electrical equipment and generators on board shipB
the earth's magnetic field affecting the ship's hard iron during constructionC
the horizontal component of the earth's magnetic field acting on the horizontal soft ironD
the vertical component of the earth's magnetic field acting on the vertical soft iron
考题
单选题Without the sun’s light ______ the earth’s surface, it would be so cold that life could not exist on the earth.A
warmsB
warmedC
warmingD
to warm
考题
单选题If the earth suddenly_______ spinning，people would all fly off it.A
had stoppedB
stoppedC
has stoppedD
would stop
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