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Practice 2 Until recently, scientists knew little about life in the deep sea, nor had they reason to believe that it was being threatened. Now, with the benefit of technology that allows for deeper exploration, researchers have uncovered a remarkable array of species inhabiting the ocean floor at depths of more than 660 feet, or about 200 meters. At the same time, however, technology has also enabled fishermen to reach far deeper than ever before, into areas where bottom trawls can destroy in minutes what has taken nature hundreds and in some cases thousands of years to build. Many of the world's coral species, for example, are found at depths of more than 200 meters. It is also estimated that roughly half of the world's highest seamounts - areas that rise from the ocean floor and are particularly rich in marine life - are also found in the deep ocean. These deep sea ecosystems provide shelter, spawning and breeding areas for fish and other creatures, as well as protection from strong currents and predators. Moreover, they are believed to harbor some of the most extensive reservoirs of life on earth, with estimates ranging from 500,000 to 100 million species inhabiting these largely unexplored and highly fragile ecosystems.
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更多 “问答题Practice 2 Until recently, scientists knew little about life in the deep sea, nor had they reason to believe that it was being threatened. Now, with the benefit of technology that allows for deeper exploration, researchers have uncovered a remarkable array of species inhabiting the ocean floor at depths of more than 660 feet, or about 200 meters. At the same time, however, technology has also enabled fishermen to reach far deeper than ever before, into areas where bottom trawls can destroy in minutes what has taken nature hundreds and in some cases thousands of years to build. Many of the world's coral species, for example, are found at depths of more than 200 meters. It is also estimated that roughly half of the world's highest seamounts - areas that rise from the ocean floor and are particularly rich in marine life - are also found in the deep ocean. These deep sea ecosystems provide shelter, spawning and breeding areas for fish and other creatures, as well as protection from strong currents and predators. Moreover, they are believed to harbor some of the most extensive reservoirs of life on earth, with estimates ranging from 500,000 to 100 million species inhabiting these largely unexplored and highly fragile ecosystems.” 相关考题
考题
187. It is hard to track the blue whale, the ocean’s largest creature, which has almost been killed off by commercial whaling and is now listed as an endangered species. Attaching radio devices to it is difficult, and visual sightings are too unreliable to give real insight into its behavior. So biologists were delighted early this year when, with the help of the Navy, they were able to track a particular blue whale for 43 days, monitoring its sounds. This was possible because of the Navy’s formerly top-secret system of underwater listening devices spanning the oceans. Tracking whales is but one example of all exciting new world just opening to civilian scientists after the cold war as the Navy starts to share and partly uncover its global network of underwater listening system built over the decades to track the ships of potential enemies. Earth scientists announced at a news conference recently that they had used the system for closely monitoring a deep-sea volcanic eruption for the first time and that they plan similar studies. Other scientists have proposed to use the network for tracking ocean currents and measuring changes in ocean and global temperatures. The speed of sound in water is roughly one mile a second, slower than through land but faster than through air. What is most important, different layers of ocean water can act as channels for sounds, focusing them in the same way a stethoscope (听诊器) does when it carries faint noises from a patient’s chest to a doctor’s ear. This focusing is the main reason that even relatively weak sounds in the ocean, especially low-frequency ones, can often travel thousands of miles. [共5题](1) The passage is chiefly about ________.(A) an effort to protect an endangered marine species(B) the exposure of a US Navy top-secret weapon(C) the civilian use of a military detection system(D) a new way to look into the behavior. of blue whales(2) The underwater listening system was originally designed ________.(A) to monitor deep-sea volcanic eruptions(B) to replace the global radio communications network(C) to study the movement of ocean currents(D) to trace and locate enemy vessels(3) The deep-sea listening system makes use of ________.(A) the unique property of layers of ocean water in transmitting sound(B) the capability of sound to travel at hligh speed(C) low-frequency sounds travelling across different layers of water(D) the sophisticated technology of focusing sounds under water(4) It can be inferred from the passage that ________.(A) blue whales are no longer endangered with the use of the new listening system(B) new radio devices should be developed for tracking the endangered blue whales(C) military technology has great potential in civilian use(D) opinions differ as to whether civilian scientists should be allowed to use military technology(5) Which of the following is true about the US Navy underwater listening network?(A) It has been replaced by a more advanced system.(B) It is now partly accessible to civilian scientists.(C) It became useless to the military after the cold war.(D) It is indispensable in protecting endangered species.
考题
AThe undersea world is very beautiful． Now more and more people want to dive in the water to find the secrets there． Scuba diving is a new sport today． It can take you into a wonder-ful undersea world．You will find many strange animals in the sea． Some are as large as a school bus． Many sea animals give out light in the dark and some have sharp teeth．During the day， there is enough light． Here， under the sea， everything is blue and green．When fish swim nearby， you can catch them with your hands． When you have bottles of air on your back， you can stay in deep water for a long time． However， you can-t dive too deep． And you must be very careful when you dive in deep water．The deep sea is not an easy place to live in． It-s cold， and it，s dark， too． The deeper it is， the less sunlight there is． At about 3，000 feet， there is no light at all． It is very dark in the sea． Many fishes have no eyes． Some have big eyes． A few have eyes on one side． Besides the cold and the darkness， deep-sea animals face a third danger-other animals．Animals eat! They must find food to eat． Many animals eat plants． However， some am-mals eat meat． This means these sea animals have two big jobs． They need to find animals as food， and they have to try not to become other animals' meal．( )21． Why do people want to dive in the sea? Because ________ ．A．they want to catch fishB． they want to find the secrets of the undersea worldC． the sea is deepD， there are all kinds of plants in the sea
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DMy father was 44 and knew he wasn’t going to male it to 45. He wrote me a letter and hoped that something in it would help me for the rest of my life.Since the day 1 was 12 and first read his letter, some of his words have lived in mybeart. One it aways times out. “Right now, you are pretending to be a time-killer. But I know that one hay, you will do something great that will set you among the very best.” Knowing that my dad believed in me gave me permission to believe in myself. “You will do something great.” He didn’t know what that would be, and neither did I, but at times in my life when I’ve felt proud of myself, I remember his words and wish he were here so I could ask. “Is this what you were talking about, Dad? Should I keep going?”A long way frim 12 now, I realize hew would have been proud when I made any progress. Lately, thongn. I’ve come to believe he’d want me to move on to winat com next: to be nrood of and believe in, somebody else. It’s time to start writing my own letters to my children. Our children look to us with the same unanswered question we had. Our kids don’t hold back because they’re afraid to fail. They’re only afraid of failing us. They don’t worry about being disappointed. Their fear－as mine was until my father’s letter－is of being a disappointment.Give your chikdren permission to succeed. They’re witing for you to believe in them. I always knew way parents loved me. But trust my That elic will be more comlece, that love will be more real, and their belief in the nelces whi be greater if you write the words on their hearts; “Don’t worry; you’ll do something great.” Not having that blessing from their parents may be the only thing holding them back.68.We learn from the text that the author .A.lost his father when he was youngB.worked hard before he read his father’s letterC.asked his father permission to believe in himselfD.knew execty at thing his father wanted him to do
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Scientists have many theories about how the universe ___ into being.A. cameB. was comingC. had comeD. would come
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What benefit is a weather bulletin to a mariner ________．A.It provides a legal reason to cancel a projected voyageB.It allows the mariner to make long term weather forecastsC.It is of little benefit since the weather changes frequently and rapidlyD.It gives the mariner time to prepare for weather changes
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In practice, it is usual for ship to be loaded _____ to improve the vessel’s movement through the water.A.a little deeper aftB.a little deeper forwardC.at the same draught between fore and aftD.a balance between two sides
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Text 3 Up until a few decades ago,our visions of the future were largely-though by no means uniformly-glowingly positive.Science and technology would cure all the ills of humanity,leading to lives of fulfillment and opportunity for all.Now utopia has grown unfashionable,as we have gained a deeper appreciation of the range of threats facing us,from asteroid strike to epidemic flu and to climate change.You might even be tempted to assume that humanity has little future to look forward to.But such gloominess is misplaced.The fossil record shows that many species have endured for millions of years-so why shouldn't we?Take a broader look at our species'place in the universe,and it becomes clear that we have an excellent chance of surviving for tens,if not hundreds,of thousands of years.Look up Homo sapiens in the"Red List"of threatened species of the International Union for the Conversation of Nature（IUCN）,and you will read:"Listed as Least Concern as the species is very widely distributed,adaptable,currently increasing,and there are no major threats resulting in an overall population decline."So what does our deep future hold?A growing number of researchers and organisations are now thinking seriously about that question.For example,the Long Now Foundation has its flagship project a medical clock that is designed to still be marking time thousands of years hence.Perhaps willfully,it may be easier to think about such lengthy timescales than about the more immediate future.The potential evolution of today's technology,and its social consequences,is dazzlingly complicated,and it's perhaps best left to science fiction writers and futurologists to explore the many possibilities we can envisage.That's one reason why we have launched Arc,a new publication dedicated to the near future.But take a longer view and there is a surprising amount that we can say with considerable assurance.As so often,the past holds the key to the future:we have now identified enough of the long-term patterns shaping the history of the planet,and our species,to make evidence-based forecasts about the situations in which our descendants will find themselves.This long perspective makes the pessimistic view of our prospects seem more likely to be a passing fad.To be sure,the future is not all rosy.But we are now knowledgeable enough to reduce many of the risks that threatened the existence of earlier humans,and to improve the lot of those to come.33.Which of the following is true according to Paragraph 5?A.Arc helps limit the scope of futurological studies.
B.Technology offers solutions to social problem.
C.The interest in science fiction is on the rise.
D.Our Immediate future is hard to conceive.
考题
Up until a few decades ago,our visions of the future were largely-though by no means uniformly-glowingly positive.Science and technology would cure all the ills of humanity,leading to lives of fulfillment and opportunity for all.Now utopia has grown unfashionable,as we have gained a deeper appreciation of the range of threats facing us,from asteroid strike to epidemic flu and to climate change.You might even be tempted to assume that humanity has little future to look forward to.But such gloominess is misplaced.The fossil record shows that many species have endured for millions of years-so why shouldn't we?Take a broader look at our species'place in the universe,and it becomes clear that we have an excellent chance of surviving for tens,if not hundreds,of thousands of years.Look up Homo sapiens in the"Red List"of threatened species of the International Union for the Conversation of Nature（IUCN）,and you will read:"Listed as Least Concern as the species is very widely distributed,adaptable,currently increasing,and there are no major threats resulting in an overall population decline."So what does our deep future hold?A growing number of researchers and organisations are now thinking seriously about that question.For example,the Long Now Foundation has its flagship project a medical clock that is designed to still be marking time thousands of years hence.Perhaps willfully,it may be easier to think about such lengthy timescales than about the more immediate future.The potential evolution of today's technology,and its social consequences,is dazzlingly complicated,and it's perhaps best left to science fiction writers and futurologists to explore the many possibilities we can envisage.That's one reason why we have launched Arc,a new publication dedicated to the near future.But take a longer view and there is a surprising amount that we can say with considerable assurance.As so often,the past holds the key to the future:we have now identified enough of the long-term patterns shaping the history of the planet,and our species,to make evidence-based forecasts about the situations in which our descendants will find themselves.This long perspective makes the pessimistic view of our prospects seem more likely to be a passing fad.To be sure,the future is not all rosy.But we are now knowledgeable enough to reduce many of the risks that threatened the existence of earlier humans,and to improve the lot of those to come.
Which of the following would be the best title for the text?A.Uncertainty about Our Future
B.Evolution of the Human Species
C.The Ever-bright Prospects of Mankind
D.Science,Technology and Humanity
考题
Text 3 Up until a few decades ago,our visions of the future were largely-though by no means uniformly-glowingly positive.Science and technology would cure all the ills of humanity,leading to lives of fulfillment and opportunity for all.Now utopia has grown unfashionable,as we have gained a deeper appreciation of the range of threats facing us,from asteroid strike to epidemic flu and to climate change.You might even be tempted to assume that humanity has little future to look forward to.But such gloominess is misplaced.The fossil record shows that many species have endured for millions of years-so why shouldn't we?Take a broader look at our species'place in the universe,and it becomes clear that we have an excellent chance of surviving for tens,if not hundreds,of thousands of years.Look up Homo sapiens in the"Red List"of threatened species of the International Union for the Conversation of Nature（IUCN）,and you will read:"Listed as Least Concern as the species is very widely distributed,adaptable,currently increasing,and there are no major threats resulting in an overall population decline."So what does our deep future hold?A growing number of researchers and organisations are now thinking seriously about that question.For example,the Long Now Foundation has its flagship project a medical clock that is designed to still be marking time thousands of years hence.Perhaps willfully,it may be easier to think about such lengthy timescales than about the more immediate future.The potential evolution of today's technology,and its social consequences,is dazzlingly complicated,and it's perhaps best left to science fiction writers and futurologists to explore the many possibilities we can envisage.That's one reason why we have launched Arc,a new publication dedicated to the near future.But take a longer view and there is a surprising amount that we can say with considerable assurance.As so often,the past holds the key to the future:we have now identified enough of the long-term patterns shaping the history of the planet,and our species,to make evidence-based forecasts about the situations in which our descendants will find themselves.This long perspective makes the pessimistic view of our prospects seem more likely to be a passing fad.To be sure,the future is not all rosy.But we are now knowledgeable enough to reduce many of the risks that threatened the existence of earlier humans,and to improve the lot of those to come.31.Our vision of the future used to be inspired byA.our desire for lives of fulfillment
B.our faith in science and technology
C.our awareness of potential risks
D.our belief in equal opportunity
考题
Text 3 Up until a few decades ago,our visions of the future were largely-though by no means uniformly-glowingly positive.Science and technology would cure all the ills of humanity,leading to lives of fulfillment and opportunity for all.Now utopia has grown unfashionable,as we have gained a deeper appreciation of the range of threats facing us,from asteroid strike to epidemic flu and to climate change.You might even be tempted to assume that humanity has little future to look forward to.But such gloominess is misplaced.The fossil record shows that many species have endured for millions of years-so why shouldn't we?Take a broader look at our species'place in the universe,and it becomes clear that we have an excellent chance of surviving for tens,if not hundreds,of thousands of years.Look up Homo sapiens in the"Red List"of threatened species of the International Union for the Conversation of Nature（IUCN）,and you will read:"Listed as Least Concern as the species is very widely distributed,adaptable,currently increasing,and there are no major threats resulting in an overall population decline."So what does our deep future hold?A growing number of researchers and organisations are now thinking seriously about that question.For example,the Long Now Foundation has its flagship project a medical clock that is designed to still be marking time thousands of years hence.Perhaps willfully,it may be easier to think about such lengthy timescales than about the more immediate future.The potential evolution of today's technology,and its social consequences,is dazzlingly complicated,and it's perhaps best left to science fiction writers and futurologists to explore the many possibilities we can envisage.That's one reason why we have launched Arc,a new publication dedicated to the near future.But take a longer view and there is a surprising amount that we can say with considerable assurance.As so often,the past holds the key to the future:we have now identified enough of the long-term patterns shaping the history of the planet,and our species,to make evidence-based forecasts about the situations in which our descendants will find themselves.This long perspective makes the pessimistic view of our prospects seem more likely to be a passing fad.To be sure,the future is not all rosy.But we are now knowledgeable enough to reduce many of the risks that threatened the existence of earlier humans,and to improve the lot of those to come.32.The IUCN’s“Red List”suggest that human being areA.a sustained species
B.a threaten to the environment
C.the world’s dominant power
D.a misplaced race
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PainAll of us have felt pain.We have cut ourselves.We have been burned.Or we have had headaches. Some of us suffer pain rarely.______(46)Pain can take complete control of our body and mind,making it impossible to move and even to think. Yet we need pain.Without it,we would not know if we have hurt ourselves.It is our body's warning system.______(47) Pain is the most common reason we go to a doctor.It is the most common reason we take medicines.Until recently,however,most doctors knew of only a few drugs that stopped some pains.______(48)But new knowledge about the process of pain is helping them to control pain better.Scientists have learned that the sense of pain is made up of both chemical and electrical signals.______(49)Scientists also have learned that the nervous system sends two different kinds of pain messages to the brain:one very fast,the other slow.The first message is the warning signal.It moves at a speed of 30 meters a second.In less than a second,the brain understands that part of the body is hurt andhow badly it is injured.______(50)It tells us not to use the injured part until it heals.______(48)A:And others have painful attacks all the time.B:These signals travel from nerve cells in the injured area , up the spinal cord（脊髓）to the brain , and back down again.C:It tells us that we are injured and should do something about it.D:They knew little about the process of pain itself.E:The other message moves at a g peed of only one meter a second.F:And they send the second,slower message of pain to the brain.
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Cloning（克隆）:Future Pertect?1 A clone is an exact copy of a plant or animal produced from any one cell.Since Scottish scientists reported that they had managed to clone a sheep named Dolly in 1997,research into cloning has grown rapidly.In May 1998,scientists in Massachusetts managed to create two identical calves（牛犊）using cloning technology. A mouse has also been cloned successfully.But the debate over cloning humans really started when Chicago physicist Richard Seed made a surprising announcement:"We will have managed to clonen a human being within the next two years."he told the world.2 Seed's announcement provoked a lot of media attention,most of it negative.In Europe, nineteen nations have already signed an agreement banning human cloning and in the U.S. the President announced:"We will be introducing a law to ban all human cloning and many states in the U.S. will have passed anti-cloning laws by the end of the year."3 Many researchers are not so negative about cloning.They are worried that laws banning human cloning will threaten important research.In March,The New England Joumal of Medicine called any plan to ban research on cloning humans seriously mistaken.Many researchers also believe that in spite of attempts to ban it,human cloning will have become routine by 2010 because it is impossible to stop the progress of science.4 Is there reason to fear that cloning will lead to a nightmare world?The public has been bombarded（轰炸）with newspaper articles , television shows and films , as well as cartoons.Such information is often misleading,and makes people wonder what on earth the scientists will be doing next.5 Within the next five to ten years scientists will probably have found a way of cioning humans.It could be that pretty soon we will be able to choose the person that we want our child to look like.But how would it feel to be a clone among hundreds,the anti-cloners ask. Pretty cool , answer the pro-cloners（赞成克隆的人）. Within ten years scientists will probably have______.A:the nucleus of a cellB:cloned human beingsC:a human being in two yearsD:a law to ban human cloningE:a report on human cloningF:heavy media coverage
考题
At the first sight the planet Mars does not appear very welcome to any kind of life．It has very little oxygen and water,the temperature at night is below-50~Cand winds of 100 miles per hour cause severe dust storms．However,the surface of the planet seems to show that water flowed across it some time in the past,and it is believed that there is enough ice at the poles to cover the planet with water if it melts．Although there is no life on the Mars now,some scientists think that there may have been some form of life long time ago．At that time,the planet had active volcanoes;the atmosphere was thicker and warmer;and there was water．In fact,in some ways the Mars may have been similar to the Earth,where life exists.
Some people believe that the Mars could support life in the future if the right conditions were produced．The first step would be to warm the planet using certain gases which trap the Sun's heat in the planet's atmosphere．With warmth,water and carbon dioxide(二氧化碳),simple plants could begin to grow．These plants could slowly make the Mars more suitable for living．It is estimated that the whole process might take between 100,000 and 200,000 years．In the meantime,people could begin to live on the planet in special closed environments．They would provide a lot of useful information about conditions on the Mars and the problems connected with living there.
Some scientists think there may have been life on the Mars in the past because__.A.there is no life there now
B.there is a large amount of water at the poles
C.the Mars may be able to support life in the future
D.conditions may have been similar to those on the Earth
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共用题干
The SeaWhat do you know about the sea?We know that it looks very pretty when the sun is shining on it.We also know that it can be very rough when there is a strong wind.What other things do we know about it?The first thing to remember is that the sea is very big.When you look at the map of the world you will find there is more water than land.The sea covers three quarters of the world.The sea is also very deep in some places.It is not deep everywhere.Some parts of the sea are very shal-low.But in some places the depth of the sea is very great.There is one spot,near Japan,where the sea is nearly 11 kilometers deep!The highest mountain in the world is about 9 kilometers high.If that mountainwere put into the sea at that place,there would be 2 kilometers of water above it！What a deep place!If you have swum in the sea,you know that it is salty.You can taste the salt,Rivers,which fi0w into the sea.carry salt from the land into the sea.Some parts of the sea are saltier than other parts,There i、one sea,called the Dead Sea,which is very salty.It is so salty that swimmers cannot sink!Fish cannot live in theDead Sea!In most parts of the sea,there are plenty of fishes and plants.Some live near the top of the sca.Othurslive deep down.There are millions of tiny living things that float in the sea.These floating things are so smallthat it is hard to see them.Many fish live by eating them.The sea can be very cold.Divers,who go deep down in the sea,know this.On the top the water may bewarm.When the diver goes downwards,the sea becomnes colder and colder. Another thing happens.When the diver goes deeper,the water above presses down on him.It squeezes him.Then the diver has to wear clothesmade of metal.But he cannot go very deep.Some people who wanted to go very deep used a very strong diving ship!They went down to the deepest part of the sea in it.They went down to a depth of eleven kilometers!The sea is 6 kilometers in depth on average.A:RightB:WrongC:Not mentioned
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共用题干
The SeaWhat do you know about the sea?We know that it looks very pretty when the sun is shining on it.We also know that it can be very rough when there is a strong wind.What other things do we know about it?The first thing to remember is that the sea is very big.When you look at the map of the world you will find there is more water than land.The sea covers three quarters of the world.The sea is also very deep in some places.It is not deep everywhere.Some parts of the sea are very shal-low.But in some places the depth of the sea is very great.There is one spot,near Japan,where the sea is nearly 11 kilometers deep!The highest mountain in the world is about 9 kilometers high.If that mountainwere put into the sea at that place,there would be 2 kilometers of water above it！What a deep place!If you have swum in the sea,you know that it is salty.You can taste the salt,Rivers,which fi0w into the sea.carry salt from the land into the sea.Some parts of the sea are saltier than other parts,There i、one sea,called the Dead Sea,which is very salty.It is so salty that swimmers cannot sink!Fish cannot live in theDead Sea!In most parts of the sea,there are plenty of fishes and plants.Some live near the top of the sca.Othurslive deep down.There are millions of tiny living things that float in the sea.These floating things are so smallthat it is hard to see them.Many fish live by eating them.The sea can be very cold.Divers,who go deep down in the sea,know this.On the top the water may bewarm.When the diver goes downwards,the sea becomnes colder and colder. Another thing happens.When the diver goes deeper,the water above presses down on him.It squeezes him.Then the diver has to wear clothesmade of metal.But he cannot go very deep.Some people who wanted to go very deep used a very strong diving ship!They went down to the deepest part of the sea in it.They went down to a depth of eleven kilometers!The land takes up 25%of the world.A:RightB:WrongC:Not mentioned
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共用题干
The SeaWhat do you know about the sea?We know that it looks very pretty when the sun is shining on it.We also know that it can be very rough when there is a strong wind.What other things do we know about it?The first thing to remember is that the sea is very big.When you look at the map of the world you will find there is more water than land.The sea covers three quarters of the world.The sea is also very deep in some places.It is not deep everywhere.Some parts of the sea are very shal-low.But in some places the depth of the sea is very great.There is one spot,near Japan,where the sea is nearly 11 kilometers deep!The highest mountain in the world is about 9 kilometers high.If that mountainwere put into the sea at that place,there would be 2 kilometers of water above it！What a deep place!If you have swum in the sea,you know that it is salty.You can taste the salt,Rivers,which fi0w into the sea.carry salt from the land into the sea.Some parts of the sea are saltier than other parts,There i、one sea,called the Dead Sea,which is very salty.It is so salty that swimmers cannot sink!Fish cannot live in theDead Sea!In most parts of the sea,there are plenty of fishes and plants.Some live near the top of the sca.Othurslive deep down.There are millions of tiny living things that float in the sea.These floating things are so smallthat it is hard to see them.Many fish live by eating them.The sea can be very cold.Divers,who go deep down in the sea,know this.On the top the water may bewarm.When the diver goes downwards,the sea becomnes colder and colder. Another thing happens.When the diver goes deeper,the water above presses down on him.It squeezes him.Then the diver has to wear clothesmade of metal.But he cannot go very deep.Some people who wanted to go very deep used a very strong diving ship!They went down to the deepest part of the sea in it.They went down to a depth of eleven kilometers!Divers have to use a very strong diving ship when they want to go down to the deepest part of the seamainly because it is extremely cold there.A:RightB:WrongC:Not mentioned
考题
共用题干
The SeaWhat do you know about the sea?We know that it looks very pretty when the sun is shining on it.We also know that it can be very rough when there is a strong wind.What other things do we know about it?The first thing to remember is that the sea is very big.When you look at the map of the world you will find there is more water than land.The sea covers three quarters of the world.The sea is also very deep in some places.It is not deep everywhere.Some parts of the sea are very shal-low.But in some places the depth of the sea is very great.There is one spot,near Japan,where the sea is nearly 11 kilometers deep!The highest mountain in the world is about 9 kilometers high.If that mountainwere put into the sea at that place,there would be 2 kilometers of water above it！What a deep place!If you have swum in the sea,you know that it is salty.You can taste the salt,Rivers,which fi0w into the sea.carry salt from the land into the sea.Some parts of the sea are saltier than other parts,There i、one sea,called the Dead Sea,which is very salty.It is so salty that swimmers cannot sink!Fish cannot live in theDead Sea!In most parts of the sea,there are plenty of fishes and plants.Some live near the top of the sca.Othurslive deep down.There are millions of tiny living things that float in the sea.These floating things are so smallthat it is hard to see them.Many fish live by eating them.The sea can be very cold.Divers,who go deep down in the sea,know this.On the top the water may bewarm.When the diver goes downwards,the sea becomnes colder and colder. Another thing happens.When the diver goes deeper,the water above presses down on him.It squeezes him.Then the diver has to wear clothesmade of metal.But he cannot go very deep.Some people who wanted to go very deep used a very strong diving ship!They went down to the deepest part of the sea in it.They went down to a depth of eleven kilometers!The deeper one goes down in the sea,the fewer fishes and plants he can find.A:RightB:WrongC:Not mentioned
考题
单选题It is implied in the passage that ______.A
many scientists had known dinoflagellate before 1988B
there had been no such organisms before 1988C
many scientists were in doubt about the nature of the organism in 1988D
no scientists knew anything about the organism in 1988
考题
单选题What is the best title for the passage?A
A Moratorium on Bottom Trawling Is Urgently Needed.B
The Oncoming Exploration to the Deep Sea.C
The Disaster of Deep Sea Life.D
Rainbow Warrior Sets Out to Save Deep Sea Life.
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问答题Practice 5 The world's oceans are slowly getting more acidic, say scientists. The researchers from California say the change is taking place in response to higher levels of carbon dioxide in the atmosphere. The lowering of the waters' pH value is not great at the moment but could pose a serious threat to current marine life if it continues, they warn. Ken Caldeira and Michael Wickett, from the Lawrence Livermore National Laboratory, report their concerns in the journal Nature. Increasing use of fossil fuels means more carbon dioxide is going into the air, and most of it will eventually be absorbed by seawater. Once in the water, it reacts to form carbonic acid. Scientists believe that the oceans have already become slightly more acidic over the last century. But these researchers have tried to predict what will happen in the future by combining what we know about the history of the oceans with computer models of climate change. "This level of acidity will get much more extreme in the future if we continue releasing CO2 into the atmosphere," said Dr Caldeira. "And we predicted amounts of future acidity that exceed anything we saw over the last several hundred million years, apart from perhaps after rare catastrophic events such as asteroid impacts." If carbon dioxide release continues unabated, ocean pH could be reduced by as much as 0.77 units, the authors warn. It is not absolutely clear what that means for marine life, however. Most organisms live near the surface, where the greatest pH change would be expected to occur, but deep-ocean lifeforms may be more sensitive to pH changes. Coral reefs and other organisms whose skeletons or shells contain calcium carbonate may be particularly affected, the team speculate. They could find it much more difficult to build these structures in water with a lower pH. In recent years some people have suggested deliberately storing carbon dioxide from power stations in the deep ocean as a way of curbing global warming. But Dr Caldeira said that such a strategy should now be re-considered. "Previously, most experts had looked at ocean absorption of carbon dioxide as a good thing — because in releasing CO2 into the atmosphere we warm the planet; and when CO2 is absorbed by the ocean, it reduces the amount of greenhouse warming.
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单选题The statement language acquisition might be our best hope (lines 68-69) means that ______.A
the ability to speak is a great asset to the survival of the human speciesB
studying how language is learned will help answer deeper questions about psychologyC
the study of linguistics is helping to make cognitive science a more popular subjectD
an individual who does not learn to speak will not develop cognitive skillsE
cognitive science has been given little notice until now
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问答题Practice 2 This portrait-gallery of old Etonians is very select: preeminent distinction of birth or merit may win you a place there, or again official connection with the school, which rightly loves to keep up an unbroken panorama of its teachers, and to vivify its annals with the faces and figures of the personalities who carried on its traditions. But how came Dolben there? It was because he was a poet, — that I knew; — and yet his poems were not known; they were jealously guarded by his family and a few friends: indeed such of his poems as could have come to the eyes of the authorities who sanctioned this memorial would not justify it. There was another reason; and the portrait bears its own credentials; for though you might not perhaps divine the poet in it, you can see the saint, the soul rapt in contemplation, the habit of stainless life, of devotion, of enthusiasm for high ideals. Such a being must have stood out conspicuously among his fellows; the facts of his life would have been the ground of the faith in his genius; and when his early death endeared and sanctified his memory, loving grief would generously grant him the laurels which he had never worn. (Robert Bridges: A School Portrait)
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问答题Practice 2 ● Recently your company is planning to bid for hosting an exhibition and now the manager of your company has asked you to write a letter to the organizing committee to introduce your company to them. ● Write a letter to introduce the details about your company. ● introducing the department structure and service, ● introducing previous exhibitions you have hosted, ● expressing your confidence in the success if you are permitted to host it.
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问答题Practice 2 Until recently, scientists knew little about life in the deep sea, nor had they reason to believe that it was being threatened. Now, with the benefit of technology that allows for deeper exploration, researchers have uncovered a remarkable array of species inhabiting the ocean floor at depths of more than 660 feet, or about 200 meters. At the same time, however, technology has also enabled fishermen to reach far deeper than ever before, into areas where bottom trawls can destroy in minutes what has taken nature hundreds and in some cases thousands of years to build. Many of the world's coral species, for example, are found at depths of more than 200 meters. It is also estimated that roughly half of the world's highest seamounts - areas that rise from the ocean floor and are particularly rich in marine life - are also found in the deep ocean. These deep sea ecosystems provide shelter, spawning and breeding areas for fish and other creatures, as well as protection from strong currents and predators. Moreover, they are believed to harbor some of the most extensive reservoirs of life on earth, with estimates ranging from 500,000 to 100 million species inhabiting these largely unexplored and highly fragile ecosystems.
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单选题In practice，it is usual for the ship to be loaded（）to improve the vessel’s movement through the water.A
a little deeper aftB
a little deeper forwardC
at the same draught between fore and aftD
a balance between two sides
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问答题Practice 6 Then came the First World War and the Second World War. (1) After each war, new ideas, new attitudes, new trades and occupations were revealed to villagers. The long-established order of society was no longer taken for granted. Electricity and the motorcar were steadily operating to make “village life” and “town life” almost alike. (2) Now with the highly developed science and technology and high-level social welfare for all, there is no point whatever in talking any longer about “village life.” It is just life, and that a better life.
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问答题Practice 6 Yet just as we are beginning to recognize the tremendous diversity of life in these areas, along with the potential benefits newly found species may hold for human society in the form of potential food products and new medicines, they are at risk of being lost forever. With enhanced ability both to identify where these species-rich areas are located and to trawl in deeper water than before, commercial fishing vessels are now beginning to reach down with nets the size of football fields, catching everything in their path while simultaneously crushing fragile corals and breaking up the delicate structure of reefs and seamounts that provide critical habitat to the countless species of fish and other marine life that inhabit the deep ocean floor. Because deep sea bottom trawling is a recent phenomenon, the damage that has been done is still limited. If steps are taken quickly to prevent this kind of destructive activity from occurring on the high seas, the benefits both to the marine environment and to future generations are incalculable. And they far outweigh the short-term costs to the fishing industry.
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