单选题The sentence “Our planet has shrunk” underlined in Paragraph 1 means that __________.A the earth has become physically smallerB the more advanced ways of traveling has made the distance between countries shorterC the traditional concept of our planet has become out-of-dateD modern means of communication has made it much easier for people to communicate with each other from different parts of the world

考题 I think a new era in the relationships between our two countries has _______.A. set aboutB. set outC. set upD. set in

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考题 Today in Hollywood ______.A. more television films are producedB. man-made fighting has completely taken the place of natural lightC. few films are taken for the cinemaD. oil production has become more important than the film industry

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考题 Most of us，when we reached our teens，started looking forward to the day when we would occupy places of our own，far from the confines of our families. We saw this moving away as a chance to strike out on our own，to grow，to spread out wings and experience freedom. At the same time，we regarded this independence as temporary-the thing to do until we found the perfect mate and married. Over the years，many millions of people have made this passage from one family to another，with just a brief，often nervous interval of independence in between. But recently，more and more people have begun to challenge the concept that living together is better than living alone. Being single is now accepted as an alternative lifestyle-one that is natural，rewarding，and complete. In fact，being single has become almost fashionable.

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考题 A greenhouse is a building made of glass which is used for keeping plants when the outside temperature is low. In a similar way there are several gases in the atmosphere which trap(捕捉)the heat produced by the sun and prevent it from escaping. These gases are known as"greenhouse gases"，and the way in which they trap heat in the atmosphere is called the "greenhouse effect". This is not simply air pollution. Most of the main greenhouse gases exist naturally in small amounts in our atmosphere, and without them earth would be 30 degrees colder and human life would not exist. In other words, the greenhouse effect is a natural course which is to some degree helpful to us.The problem is that in the last century and a half, we have been putting too many of these gases into the earth's atmosphere by burning large quantities of coal and oil and by cutting down forests. The rapid increase in greenhouse gases is making the world warmer. The world's temperature has already gone up by half a degree this century, and the sea level has risen by 10 centimetres. If the amount of carbon dioxide(二氧化碳)in the atmosphere doubles, there will probably be a rise in the earth's temperature of between 1 and 4 degrees. This may seem a small increase, but it would be enough to cause major changes in geography and agriculture. Large areas of the world would be flooded, and some areas would become dry and unable to produce crops. It is important, too, to consider that there may be a delay of about 30 years in the greenhouse effect. This means that we are probably experiencing only now the effect of the gases put into the atmosphere before the 1960s. Since then, our use of these gases has greatly increased.1. The"greenhouse effect"means _____.A. the way in which gases are used for keeping plants warmB. a natural course which is some degree helpful to usC. the way"greenhouse gases"trap heat on the earthD. the whole course in which greenhouse gases prevent heat2. If there were no greenhouse effect, _____.A. no plants would grow on our planetB. earth would be thirty degrees colderC. man could not live on the earthD. All of the above answers are correct3. Which of the following is NOT true? _____A. Burning too much coal and oil produces lots of greenhouse gases.B. It has become warmer on the earth now than in the past.C. Gases put into the atmosphere now will affect the earth years later.D. The temperature in a greenhouse is as high as that in the atmosphere.4. Suppose the earth's temperature rose by 3 degrees, _____.A. great harm would be done to mankindB. the sea level would go by 10 centimetresC. all the land in the world would be floodedD. crops would be unable to grow on the earth5. This passage mainly deals with _____.A. the concept(概念)and harm of greenhouse effectB. the relation between greenhouse gases and manC. the concept and change of greenhouse effectD. the effect of the rise of the earth's temperature

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考题 There is only one kind of family on planet Earth today: it is the traditional extended family.()

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考题 Our teacher told us that the earth _____ from west to east. A、turnB、turnsC、turnedD、has turned

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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. On Venus there is a lot of__________.A. water B. carbon dioxide C. carbon monoxide D. oxygen

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考题共用题干 Earth's Inner CoreScientists have long struggled to understand what lies at the planet's center.Direct observation of its center is impossible,so researchers must_________(1)to other evidence.In 1889,a German scientist detected a severe earthquake in Japan.Geophysicists concluded that shock waves_________(2) jolts（晃动）from one side of Earth through the center to the other side.Then in 1936,Danish geophysicist lnge Lehmann studied the waves' __________ (3) to determine that within Earth's core of molten（熔化了的）iron lies a solid inner core一but_________(4) that core was made of eluded（难倒）her. Other geophysicists quickly determined that Lehmann's inner core was composed mostly_________(5) iron.Since then,Lehmann's discovery has _________(6) conventional Earth science.But now scientists are challenging traditional theory with new and radical_________(7).For example,Earth's center could actually contain an"inner core within the inner core."claim lshii and colleague Adam Dziewonski.Analyzing hundreds of thousands of earthquake wave _________(8),they maintain that the inner core has at its heart a tiny, even more solid sphere（球体）.This sphere"may be the oldest fossil_________(9)from the formation of Earth,"says Dziewonski.Dziewonski and Ishii speculate that shortly _________(10)Earth formed around 4.8 billion years ago,a giant asteroid（小行星）smashed into the young planet and nearly melted it.But Earth's center didn't quite melt;it_________(11)mass as the planet cooled. The core within a core may be the kernel（核心）that endured. " Its presence could change our basic ideas about the_________(12)of the planet,"Dziewonski says.Dziewonski's idea is tame（温和的）compared to the_________( 13 ) theories ofindependent geophysicist J. Marvin Herndon.Earth's inner core is made not of iron,he claims,but a_________(14)of nickel and silicon.Herndon has a truly revolutionary notion : Within the nickel silicide（硅化物）inner core is also an "inner" inner core一an 8km-wide ball of the element uranium.Uranium is radioactive.Herndon thinks the uranium releases heat energy as its atoms_________(15)fission-split and crash into one another in a chain reaction.In other words,we may live on top of a gigantic, "natural" nuclear power plant._________(1)A:try B:leave C:turn D:point

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考题共用题干 Earth's Inner CoreScientists have long struggled to understand what lies at the planet's center.Direct observation of its center is impossible,so researchers must_________(1)to other evidence.In 1889,a German scientist detected a severe earthquake in Japan.Geophysicists concluded that shock waves_________(2) jolts（晃动）from one side of Earth through the center to the other side.Then in 1936,Danish geophysicist lnge Lehmann studied the waves' __________ (3) to determine that within Earth's core of molten（熔化了的）iron lies a solid inner core一but_________(4) that core was made of eluded（难倒）her. Other geophysicists quickly determined that Lehmann's inner core was composed mostly_________(5) iron.Since then,Lehmann's discovery has _________(6) conventional Earth science.But now scientists are challenging traditional theory with new and radical_________(7).For example,Earth's center could actually contain an"inner core within the inner core."claim lshii and colleague Adam Dziewonski.Analyzing hundreds of thousands of earthquake wave _________(8),they maintain that the inner core has at its heart a tiny, even more solid sphere（球体）.This sphere"may be the oldest fossil_________(9)from the formation of Earth,"says Dziewonski.Dziewonski and Ishii speculate that shortly _________(10)Earth formed around 4.8 billion years ago,a giant asteroid（小行星）smashed into the young planet and nearly melted it.But Earth's center didn't quite melt;it_________(11)mass as the planet cooled. The core within a core may be the kernel（核心）that endured. " Its presence could change our basic ideas about the_________(12)of the planet,"Dziewonski says.Dziewonski's idea is tame（温和的）compared to the_________( 13 ) theories ofindependent geophysicist J. Marvin Herndon.Earth's inner core is made not of iron,he claims,but a_________(14)of nickel and silicon.Herndon has a truly revolutionary notion : Within the nickel silicide（硅化物）inner core is also an "inner" inner core一an 8km-wide ball of the element uranium.Uranium is radioactive.Herndon thinks the uranium releases heat energy as its atoms_________(15)fission-split and crash into one another in a chain reaction.In other words,we may live on top of a gigantic, "natural" nuclear power plant._________(12)A:size B:origin C:structure D:shape

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考题 And that quest has brought______benefits that improve our lives in countless ways. A.tangible B.displayed C.conditional D.proved

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考题共用题干 A Record-Breaking RoverNASA's Mars rover Opportunity has boldly gone where no rover has gone before—at least in terms of distance. Since arriving on the Red Planet in 2004,Opportunity has traveled 25 .01 miles,more than any other wheeled vehicle has on another world.“This is so remarkable considering Opportunity was intended to drive about 1 kilometer and was never designed for distance,”says John Callas,the Mars Exploration Rover Project Manager.He works at NASA's Jet Propulsion Laboratory in Pasadena,California.“But what is really importantly is not how many miles the rover has racked up,but how much exploration and discovery we have accomplished over that distance.”The solar-powered Opportunity and its twin rover,Spirit,landed on Mars 10 years ago on a mission expected to last 3 months. The objective of the rovers was to help scientists learn more about the planet and to search for signs of life,such as the possible presence of water.Spirit stopped communicating with Earth in March 2010,a few months after it got stuck in a sand pit. But Opportunity has continued to collect and analyze Martian soil and rocks.During its mission,Opportunity has captured,and sent back to Earth,some 187,000 panoramic and microscopic images of Mars with its cameras. It has also provided scientists with data on the planet's atmosphere,soil,rocks,aid terrain.The rover doesn't seem to be ready to stop just yet. If Opportunity can continue on,it will reach another major investigation site when its odometer hits 26.2 miles. Opportunity has beer working on Mars since January 2004.Researchers believe that clay minerals exposed near Marathon Valley could hold clues to Mars's ancient environment. Opportunity's continuing travels will also help researchers as the, plan for an eventual human mission to the Red Planet. Which of the following statements is true of Opportunity?A: It will come back to earth soon.B: Another rover will be sent to replace it.C: It is travelling to another major investigation site.D: It will work with other rovers exploring Mars.

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考题共用题干 A Record-Breaking RoverNASA's Mars rover Opportunity has boldly gone where no rover has gone before—at least in terms of distance. Since arriving on the Red Planet in 2004,Opportunity has traveled 25 .01 miles,more than any other wheeled vehicle has on another world.“This is so remarkable considering Opportunity was intended to drive about 1 kilometer and was never designed for distance,”says John Callas,the Mars Exploration Rover Project Manager.He works at NASA's Jet Propulsion Laboratory in Pasadena,California.“But what is really importantly is not how many miles the rover has racked up,but how much exploration and discovery we have accomplished over that distance.”The solar-powered Opportunity and its twin rover,Spirit,landed on Mars 10 years ago on a mission expected to last 3 months. The objective of the rovers was to help scientists learn more about the planet and to search for signs of life,such as the possible presence of water.Spirit stopped communicating with Earth in March 2010,a few months after it got stuck in a sand pit. But Opportunity has continued to collect and analyze Martian soil and rocks.During its mission,Opportunity has captured,and sent back to Earth,some 187,000 panoramic and microscopic images of Mars with its cameras. It has also provided scientists with data on the planet's atmosphere,soil,rocks,aid terrain.The rover doesn't seem to be ready to stop just yet. If Opportunity can continue on,it will reach another major investigation site when its odometer hits 26.2 miles. Opportunity has beer working on Mars since January 2004.Researchers believe that clay minerals exposed near Marathon Valley could hold clues to Mars's ancient environment. Opportunity's continuing travels will also help researchers as the, plan for an eventual human mission to the Red Planet. Opportunity is a record breaking rover in the sense of________.A: how long is has stayed in spaceB: how far it has traveledC: how much investment it has involvedD: how many facilities it has been equipped with

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考题共用题干 A Record-Breaking RoverNASA's Mars rover Opportunity has boldly gone where no rover has gone before—at least in terms of distance. Since arriving on the Red Planet in 2004,Opportunity has traveled 25 .01 miles,more than any other wheeled vehicle has on another world.“This is so remarkable considering Opportunity was intended to drive about 1 kilometer and was never designed for distance,”says John Callas,the Mars Exploration Rover Project Manager.He works at NASA's Jet Propulsion Laboratory in Pasadena,California.“But what is really importantly is not how many miles the rover has racked up,but how much exploration and discovery we have accomplished over that distance.”The solar-powered Opportunity and its twin rover,Spirit,landed on Mars 10 years ago on a mission expected to last 3 months. The objective of the rovers was to help scientists learn more about the planet and to search for signs of life,such as the possible presence of water.Spirit stopped communicating with Earth in March 2010,a few months after it got stuck in a sand pit. But Opportunity has continued to collect and analyze Martian soil and rocks.During its mission,Opportunity has captured,and sent back to Earth,some 187,000 panoramic and microscopic images of Mars with its cameras. It has also provided scientists with data on the planet's atmosphere,soil,rocks,aid terrain.The rover doesn't seem to be ready to stop just yet. If Opportunity can continue on,it will reach another major investigation site when its odometer hits 26.2 miles. Opportunity has beer working on Mars since January 2004.Researchers believe that clay minerals exposed near Marathon Valley could hold clues to Mars's ancient environment. Opportunity's continuing travels will also help researchers as the, plan for an eventual human mission to the Red Planet. It can be inferred from the last paragraph that＿________.A: experts know how far Opportunity will make in MarsB:.reseachers are working on sending many more humans to MarsC: Mars's ancient environment might be exposed with the help of OpportunityD: Opportunity is supposed to collect clay minerals from Marathon Valley

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考题共用题干 A Record-Breaking RoverNASA's Mars rover Opportunity has boldly gone where no rover has gone before—at least in terms of distance. Since arriving on the Red Planet in 2004,Opportunity has traveled 25 .01 miles,more than any other wheeled vehicle has on another world.“This is so remarkable considering Opportunity was intended to drive about 1 kilometer and was never designed for distance,”says John Callas,the Mars Exploration Rover Project Manager.He works at NASA's Jet Propulsion Laboratory in Pasadena,California.“But what is really importantly is not how many miles the rover has racked up,but how much exploration and discovery we have accomplished over that distance.”The solar-powered Opportunity and its twin rover,Spirit,landed on Mars 10 years ago on a mission expected to last 3 months. The objective of the rovers was to help scientists learn more about the planet and to search for signs of life,such as the possible presence of water.Spirit stopped communicating with Earth in March 2010,a few months after it got stuck in a sand pit. But Opportunity has continued to collect and analyze Martian soil and rocks.During its mission,Opportunity has captured,and sent back to Earth,some 187,000 panoramic and microscopic images of Mars with its cameras. It has also provided scientists with data on the planet's atmosphere,soil,rocks,aid terrain.The rover doesn't seem to be ready to stop just yet. If Opportunity can continue on,it will reach another major investigation site when its odometer hits 26.2 miles. Opportunity has beer working on Mars since January 2004.Researchers believe that clay minerals exposed near Marathon Valley could hold clues to Mars's ancient environment. Opportunity's continuing travels will also help researchers as the, plan for an eventual human mission to the Red Planet. What does John Callas say about Opportunity's long distance travel?A: It hasn't met scientists' expectation yetB: It hasn't been appreciated appropriatelyC: It is secondary to what has been discoveredD:.It is what scientists have been aiming at

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考题共用题干 A Record-Breaking RoverNASA's Mars rover Opportunity has boldly gone where no rover has gone before—at least in terms of distance. Since arriving on the Red Planet in 2004,Opportunity has traveled 25 .01 miles,more than any other wheeled vehicle has on another world.“This is so remarkable considering Opportunity was intended to drive about 1 kilometer and was never designed for distance,”says John Callas,the Mars Exploration Rover Project Manager.He works at NASA's Jet Propulsion Laboratory in Pasadena,California.“But what is really importantly is not how many miles the rover has racked up,but how much exploration and discovery we have accomplished over that distance.”The solar-powered Opportunity and its twin rover,Spirit,landed on Mars 10 years ago on a mission expected to last 3 months. The objective of the rovers was to help scientists learn more about the planet and to search for signs of life,such as the possible presence of water.Spirit stopped communicating with Earth in March 2010,a few months after it got stuck in a sand pit. But Opportunity has continued to collect and analyze Martian soil and rocks.During its mission,Opportunity has captured,and sent back to Earth,some 187,000 panoramic and microscopic images of Mars with its cameras. It has also provided scientists with data on the planet's atmosphere,soil,rocks,aid terrain.The rover doesn't seem to be ready to stop just yet. If Opportunity can continue on,it will reach another major investigation site when its odometer hits 26.2 miles. Opportunity has beer working on Mars since January 2004.Researchers believe that clay minerals exposed near Marathon Valley could hold clues to Mars's ancient environment. Opportunity's continuing travels will also help researchers as the, plan for an eventual human mission to the Red Planet. One of the objectives of sending Opportunity and Spirit is to＿________.A: collect soil and send back to EarthB: develop multinational space explorationC:.test how well solar-powered rovers work in outer spaceD: look for the possible presence of life

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考题我们的重吊杆已经长时间不用了。（）A、Our derrick has been out of use for a long time.B、Our heavy derrick has been out of use for a long time.C、Our crane has been out of use for a long time.D、Our winch has been out of use for a long time.

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考题单选题Stephen Hawking believes that earth is unlikely to be the only planet ______ life has developed gradually.A thatB whereC whichD whose

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考题单选题The sentence “Our planet has shrunk” underlined in Paragraph 1 means that.A the earth has become physically smallerB the more advanced ways of traveling has made the distance between countries shorterC the traditional concept of our planet has become out-of-dateD modern means of communication has made it much easier for people to communicate with each other from different parts of the world

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考题单选题The greatest chance for the existence of extraterrestrial life is on a planet beyond our solar system. The Milky Way galaxy alone contains 100 billion other suns, many of which could be accompanied by planets similar enough to Earth to make them suitable abodes of life.　 The statement above assumes which of the following?A Living creatures on another planet would probably have the same appearance as those on Earth.B Life cannot exist on other planets in our solar system.C If the appropriate physical conditions exist, life is an inevitable consequence.D More than one of the suns in the galaxy is accompanied by an Earth-like planet.E It is likely that life on another planet would require conditions similar to those on Earth.

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考题单选题The sentence “But this has rarely been a one-way street.” in the last paragraph means that _____.A contemporary art has been nourished by modern scienceB modern science has been nourished by artC artists can become scientists and scientists can become artistsD the impacts of modern art and science are actually mutual

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考题单选题_____ our great surprise, our company has made much more profit than we expected last year.A ForB InC WithD To

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考题单选题______ our great surprise, our company has made much more profit than we expected lastyear.A ForB InC WithD To

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考题单选题Geological evidence suggests that the earth’s magnetic polarity has switched back and forth many times over the millennia; such ______in the magnetic field may affect the ability of our planet to ward off cosmic radiation.A intensificationsB justificationsC recordsD correlationsE fluctuations

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考题单选题Is _____ 48 hours _____ the man-made satellite _____ is made in our country to orbit the planet around?A it; that; whereB it; when; whatC it for; that it takes; thatD it; that it takes; which

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考题单选题_____ from space, our earth, with water covering 70% of its surface, appears as a “blue planet”.A SeeingB To be seenC SeenD Having seen

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考题单选题What has happened in the past half-century?A The population of 15 countries has reduced by more than half.B Many countries have made unprecedented economic progress.C Many countries are still struggling with underdevelopment.D Urbanization has been taking place at a fast pace.

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考题单选题_____from space, our earth, with water covering 70% of its surface, appears as a blue planet.A SeeingB To be seenC SeenD Having seen

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