单选题We may infer from the fourth paragraph that ______.A humans have been growing food crops more than ten thousand years.B humans have learned how to produce biofuels for a long time.C humans are just on the beginning of making biofuels.D a cell wall includes four hemicellulose.

考题 What can we infer from the last paragraph?[A] Monkeys can be trained to develop social emotions.[B] Human indignation evolved from an uncertain source.[C] Animals usually show their feelings openly as humans do.[D] Cooperation among monkeys remains stable only in the wild.

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考题 Compared to other mammals, humans have relatively long life _________.A． lengthB． extensionC． expenseD． span

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考题 Robots have one advantage over humans-they never ____ lack of sleep or food.A.benefit fromB.suffer fromC.stem fromD.result from

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考题 BAsk someone what they have done to help the environment recently and they will almost certainly mention recycling. Recycling in the home is very important of course. However, being forced to recycle often means we already have more material than we need. We are dealing with the results of that over-consumption in the greenest way possible, but it would be far better if we did not need to bring so much material home in the first place.The total amount of packaging increased by 12% between 1999 and 2005. It now makes up a third of a typical household’s waste in the UK. In many supermarkets nowadays food items are packaged twice with plastic and cardboard.Too much packaging is doing serious damage to the environment. The UK, for example, is running out of it for carrying this unnecessary waste. If such packaging is burnt, it gives off greenhouse gases which go on to cause the greenhouse effect. Recycling helps, but the process itself uses energy. The solution is not to produce such items in the first place. Food waste is a serious problem, too. Too many supermarkets encourage customers to buy more than they need. However, a few of them are coming round to the idea that this cannot continue , encouraging customers to reuse their plastic bags, for example.But this is not just about supermarkets. It is about all of us. We have learned to associate packaging with quality. We have learned to think that something unpackaged is of poor quality. This is especially true of food. But is also applies to a wide range of consumer products, which often have far more packaging than necessary.There are signs of hope. As more of us recycle, we are beginning to realise just how much unnecessary material are collecting. We need to face the wastefulness of our consumer culture, but we have a mountain to climb.61. What does the underlined phrase “over-consumption” refer to?A. Using too much packaging.B. Recycling too many wastes.C. Making more products than necessary.D. Having more material than is needed.

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考题 From the last paragraph we can learn that __A. some pipes have to be re-arranged in winterB. the system can do more than warming up the buildingC. the exchangers will pick up heat from the street surfaceD. less heat may be collected in winter than in summer

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考题 EA rainforest is an area covered by tall trees with the total high rainfall spreading quite equally through the year and the temperature rarely dipping below l6℃．Rainforests have a great effect on the world environment because they can take in heat from the sun and adjust the climate．Without the forest cover，these areas would reflect more heat into the atmosphere，warming the rest of the world. Losing the rainforests may also influence wind and rainfall patterns，potentially causing certain natural disasters all over the world．In the past hundred years，humans have begun destroying rainforests in search of three major resources(资源)：land for crops，wood for paper and other products，land for raising farm animals．This action affects the environment as a whole．For example，a lot of carbon dioxide (二氧化碳)in the air comes from burning the rainforests．People obviously have a need for the resources we gain from cutting trees but we will suffer much more than we will benefit.There are two main reasons for this．Firstly，when people cut down trees，generally they can only use the land for a year or two．Secondly，cutting large sections of rainforests may provide a good supply of wood right now，but in the long run it actually reduces the world’s wood supply．Rainforests are often called the world’s drug store．More than 25％ of the medicines we use today come from plants in rainforests．However，fewer than l％of rainforest plants have been examined for their medical value．It is extremely likely that our best chance to cure diseases lies somewhere in the world’s shrinking rainforests．72．Rainforests can help to adjust the climate because they ．A．reflect more heat into the atmosphereB．bring about high rainfall throughout the worldC．rarely cause the temperature to drop lower than l6℃D．reduce the effect of heat from the sun on the earth

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考题 What does the word “this” underlined in the third paragraph refer to?A．We will lose much more than we can gain．B．Humans have begun destroying rainforests．C．People have a strong desire for resources．D．Much carbon dioxide comes from burning rainforests．

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考题 What can be inferred from Paragraph 3?A.Body language is uniqun to humans.B.Animals express emotions just as humans do.C.Humans have other poeers of communication.D.Humans are thfferent from animals to some degree.

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考题 We can infer from the third paragraph that _____.［A］ rich people are more interested in cloning humans than animals［B］ cloning of animal pets is becoming a prosperous industry［C］ there is no distinction between a cloned and a natural dog［D］ Missy’s master pays a lot in a hope to revive the dog

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考题 (41~45) Researchers have found that drugs used to treat human seizures can delay aging in worms by as much as 50 percent. The roundworms used for the study are similar to humans in their molecular makeup, raising thepossibility that the drugs could also extend the life span of humans。第41题：“By finding a class of drugs that delays aging we have found a relationship between the function of the nervous system and aging that was not well understood, ” said Kerry Komfeld, a geneticist at the Washington University School of Medicine in St. Louis, Missouri. The findings are detailed this week in the journal Science。 The discovery came out of the thesis work by one of Komfeld’s graduate students, Kimberley Evason. About four years ago, Evason began exposing groups of the roundworm Caenorhabditis elegans to commercially available drugs to see if the drugs would delay aging or promote longevity。A. But Komfeld said scientists will not know about the applicability of the drugs in humans until a similar study is done on humans. “What’s very encouraging is that these drugs were developed to treat humans, and they are well understood, because they’ve been used for a long time, ” he said。B. Later the scientists discovered that two related anticonvulsant drugs also lengthened the lives of the worms-in the case of one drug, by almost 50 percent. “This was a big surprise to use, Komfeld said. ”“We didn’t think anticonvulsant drugs had any particular relationship to aging. That connection was completely unexpected. ”C. Roundworms are a poor subject for experiments, because they are not like humans, even though their molecules are similar. For example, they have no bones, nor do they show emotions, making it difficult to know how exactly human subjects would react to these drugs in large quantities. However, using the worms allows experiments to be conducted quickly, because they do not live for long。D. “Somehow the neural activity seems to regulate the aging of all of the body the skin, musculature, and reproductive tract, ” Kornfeld said. “Somehow the nervous system coordinates the progress of all these tissues, evidently, though the life stages. But we don’t know how it does that. ”E. The discovery may also shed light on the little-understood aging process. Since the drugs act on the neuromuscular systems of both humans and worms, the findings hint at a link between neural activity and aging。F. Unlike vertebrates, the worms are ideal subjects for the study of aging because of their short life spans, which last only a couple of weeks in a laboratory. The worm is well known in genetics, and the worm’s genome has been sequenced。G. Use of this drug has been permitted by law since 1998 and wider use is now expected as a result of the studies. “We can clearly link this drug with human aging, but we still need to find proof, says Kornfeld optimistically. ”

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考题 The discovery that the drugs extend the life span of roundworms could have important implications fox human aging as well. There are strong similarities on the molecular level between the proteins and genes thatA. But Komfeld said scientists will not know about the applicability of the drugs in humans until a similar study is done on humans. “What’s very encouraging is that these drugs were developed to treat humans, and they are well understood, because they’ve been used for a long time, ” he said。B. Later the scientists discovered that two related anticonvulsant drugs also lengthened the lives of the worms-in the case of one drug, by almost 50 percent. “This was a big surprise to use, Komfeld said. ”“We didn’t think anticonvulsant drugs had any particular relationship to aging. That connection was completely unexpected. ”C. Roundworms are a poor subject for experiments, because they are not like humans, even though their molecules are similar. For example, they have no bones, nor do they show emotions, making it difficult to know how exactly human subjects would react to these drugs in large quantities. However, using the worms allows experiments to be conducted quickly, because they do not live for long。D. “Somehow the neural activity seems to regulate the aging of all of the body the skin, musculature, and reproductive tract, ” Kornfeld said. “Somehow the nervous system coordinates the progress of all these tissues, evidently, though the life stages. But we don’t know how it does that. ”E. The discovery may also shed light on the little-understood aging process. Since the drugs act on the neuromuscular systems of both humans and worms, the findings hint at a link between neural activity and aging。F. Unlike vertebrates, the worms are ideal subjects for the study of aging because of their short life spans, which last only a couple of weeks in a laboratory. The worm is well known in genetics, and the worm’s genome has been sequenced。G. Use of this drug has been permitted by law since 1998 and wider use is now expected as a result of the studies. “We can clearly link this drug with human aging, but we still need to find proof, says Kornfeld optimistically. ”

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考题 There may also be other targets not yet explored that affect aging and neuromuscular function. Said Kornfeld: “The process of aging remains mysterious. ”A. But Komfeld said scientists will not know about the applicability of the drugs in humans until a similar study is done on humans. “What’s very encouraging is that these drugs were developed to treat humans, and they are well understood, because they’ve been used for a long time, ” he said。B. Later the scientists discovered that two related anticonvulsant drugs also lengthened the lives of the worms-in the case of one drug, by almost 50 percent. “This was a big surprise to use, Komfeld said. ”“We didn’t think anticonvulsant drugs had any particular relationship to aging. That connection was completely unexpected. ”C. Roundworms are a poor subject for experiments, because they are not like humans, even though their molecules are similar. For example, they have no bones, nor do they show emotions, making it difficult to know how exactly human subjects would react to these drugs in large quantities. However, using the worms allows experiments to be conducted quickly, because they do not live for long。D. “Somehow the neural activity seems to regulate the aging of all of the body the skin, musculature, and reproductive tract, ” Kornfeld said. “Somehow the nervous system coordinates the progress of all these tissues, evidently, though the life stages. But we don’t know how it does that. ”E. The discovery may also shed light on the little-understood aging process. Since the drugs act on the neuromuscular systems of both humans and worms, the findings hint at a link between neural activity and aging。F. Unlike vertebrates, the worms are ideal subjects for the study of aging because of their short life spans, which last only a couple of weeks in a laboratory. The worm is well known in genetics, and the worm’s genome has been sequenced。G. Use of this drug has been permitted by law since 1998 and wider use is now expected as a result of the studies. “We can clearly link this drug with human aging, but we still need to find proof, says Kornfeld optimistically. ”

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考题 We can infer from Paragraph 5 that ______.（）[A] home prices has fallen down 28% compared with what's in mid-2006[B] many foreclosed homes have been abandoned by their former owners[C] home prices might fall down 28% fi'om their peak in mid-2006 in the future[D] more foreclosed homes have been abandoned because of the falling price

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考题共用题干第二篇Natural MedicinesSince earliest days,humans have used some kinds of medicines.We know this because humans have survived.Ancient treatments for injury and disease were successful enough to keep humans from dying out completely.They were successful long before the time of modern medicine.Before the time of doctors with white coats and shiny（发亮的）instruments. Before the time of big hospitals with strange and wonderful equipment.Many parts of the world still do not have university-educated doctors. Nor do they have expensive hospi- tals.Yet injuries are treated.And diseases are often cured.How?By ancient methods.By medicines that might seem mysterious , even magical（有魔力的）.Traditional medicines are neither mysterious nor magical, however.Through the centuries, tribal（部族的）medicine men experimented with plants. They found many use- ful chemicals in the plants.And scientists believe many of these traditional medicines may provide the cure for some of today's most serious diseases.Experts say almost 80% of the people in the world use plants for health care.These natural medicines are used not just because people have no other form of treatment.They are used because people trust them. In developed areas,few people think about the source of the medicines they buy in a store.Yet many wide- ly-used medicines are from ancient sources,especially plants.Some experts say more than 25% of modern medicines come,in one way or another,from nature.Scientists have long known that nature is really a chemical factory.All living things contain chemicals that help them survive.So scientists' interest in traditional medicine is not new.But it has become an ur-gent concern.This is because the earth's supply of natural medicines may be dropping rapidly. It can be seen from the passage that the earth's supply of natural medicines________.A:may never be exhaustedB:may be dropping rapidlyC:is surprisingly bigD:is as rich as ever

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考题共用题干第二篇Natural MedicinesSince earliest days,humans have used some kinds of medicines.We know this because humans have survived.Ancient treatments for injury and disease were successful enough to keep humans from dying out completely.They were successful long before the time of modern medicine.Before the time of doctors with white coats and shiny（发亮的）instruments. Before the time of big hospitals with strange and wonderful equipment.Many parts of the world still do not have university-educated doctors. Nor do they have expensive hospi- tals.Yet injuries are treated.And diseases are often cured.How?By ancient methods.By medicines that might seem mysterious , even magical（有魔力的）.Traditional medicines are neither mysterious nor magical, however.Through the centuries, tribal（部族的）medicine men experimented with plants. They found many use- ful chemicals in the plants.And scientists believe many of these traditional medicines may provide the cure for some of today's most serious diseases.Experts say almost 80% of the people in the world use plants for health care.These natural medicines are used not just because people have no other form of treatment.They are used because people trust them. In developed areas,few people think about the source of the medicines they buy in a store.Yet many wide- ly-used medicines are from ancient sources,especially plants.Some experts say more than 25% of modern medicines come,in one way or another,from nature.Scientists have long known that nature is really a chemical factory.All living things contain chemicals that help them survive.So scientists' interest in traditional medicine is not new.But it has become an ur-gent concern.This is because the earth's supply of natural medicines may be dropping rapidly. The passage indicates that ancient treatments for injury and disease were_________.A:much more successful than modern onesB:successful enough for humans to surviveC:successful in all casesD:of little help to humans

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考题 Text3 Genetically engineered crops are safe for humans and animals to eat and have not caused increases in cancer,obesity,gastrointestinal illnesses,kidney disease,autism or allergies,an exhaustive report from the National Academies of Science released Tuesday found.Overall,genetically engineered（GE）crops saved farmers in the United States money but didn't appear to increase crop yields.They have lowered pest populations in some areas,especially in the Midwest but increased the number of herbicide-resistant weeds in others.There's also no evidence that GE crops have affected the population of monarch butterflies,the report said.To gauge whether foods made from genetically modified crops were safe for human consumption,the committee compared disease reports from the United States and Canada,where such crops have been consumed since the mid-1990s,and those in the United Kingdom and westem Europe,where they are not widely eaten.No long-term pattem ofincrease in specific health problems after the introduction of GE foods in the 1990s in the United States and Canada was found.There was no correlation between obesity or Type n diabetes and the consumption of GE foods.Celiac disease,which makes humans intolerant of gluten,increased in both populations.Patterns in the increase in autism spectrum disorder in children were similar in both the United Kingdom and the United States,the committee reported.Overall the report concluded that there were no differences in terms ofa higher risk to human health between foods made from GE crops and those made from conventionally-bred crops.Food&Water Watch,a government accountability group in Washington D.C.,said the committee's ties to the biotech industry and other corporations create conflicts ofinterest and raise questions about the independence ofits work."Critics have long been marginalized,"said Wenonah Hauter,the group's executive director.A significant portion of American consumers are concerned about the safety or other effects of foods made with genetically modified crops,often called GMOs for genetically modified orgarusms.A survey released last year by the NPD Group,a market research firm,found that 57%ofAmericans were concemed that genetically modified foods posed a health hazard.The food industry has taken notice.In 2015,Progressive Grocer,a trade publication,reported that total U.S.sales of food and beverage products labeled"non-GMO"reached$10 billion during 2014.The National Academies report will likely not sway these consumers,said Phil Lempert,a Los Angeles-based food industry analyst."It's an emotional issue,it's not a science issue,"he said.32.According to Paragraphs 3 and 4,we can infer thatA.European people have widely accepted GE crops. B.GE crops have been introduced to Britain in the 1990s. C.Celiac disease has relationship to GE crops consumption. D.People in UK and U.S.have suffered from overweight.

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考题共用题干 Natural MedicinesSince earliest days,humans have used some kinds of medicines.We know this because hu-mans have survived .Ancient treatments for injury and disease were successful enough to keep hu-mans from dying out completely.They were successful long before the time of modern medicine.Before the time of doctors with white coats and shiny（发亮的）instruments. Before the time of big hospitals with strange and wonderful equipment.Many parts of the world still do not have university-educated doctors.Nor do they have ex- pensive hospitals.Yet injuries are treated.And diseases are often cured.How?By ancient meth- ods. By medicines that might seem mysterious, even magical（有魔力的）.Traditional medicines are neither mysterious nor magical,however.Through the centuries, tribal（部落的）medicine men experimented with plants. They found many useful chemicals in the plants.And scientists believe many of these traditional medicines may provide the cure for some of today's most serious diseases.Experts say almost 80%of the people in the world use plants for health care.These natural medicines are used not just because people have no other form of treatment.They are used be-cause people trust them.In developed areas,few people think about the source of the medicines they buy in a store.Yet many widely-used medicines are from ancient sources,especially plants. Some experts say more than 25%of modern medicines come,in one way or another,from nature.Scientists have long known that nature is really a chemical factory.All living things contain chemicals that help them survive .So scientists' interest in traditional medicine is not new.But it has become an urgent concern.This is because the earth's supply of natural medicines may be dropping rapidly. The passage indicates that ancient treatments for injury and disease were_____.A: much more successful than modern onesB: successful enough for humans to surviveC: successful in all casesD: of little help to humans

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考题资料：It’s easy to trace the evolution of the automobile.At most，we’re only talking about a few centuries of technological development，and most of the plans，prototypes and models are still around. With just a little research，you can easily trace the latest model electric hybrid back to its steam-powered ancestors. Your family tree is probably a different matter. Even an extensive genealogy chart can only reach back so far，and mortality puts a rather strict limit on exactly how many “models” are still on the road. Humanity’s evolutionary progression is even more difficult. We still have plenty of living primate relatives，but many of the life forms that connect the evolutionary dots are long extinct. Evolutionary biologists use several methods to decipher exactly how we came to be as we are.In fact，the field itself encompasses several different disciplines in addition to biology，like genetics，psychology，geology，archaeology linguistics，anthropology and primatology just to name a few. Naturally，paleoanthropology also plays a key role，as we have to turn to the fossil record for many clues about our ancient primate，human and nearly human ancestors. While the fossil record by its very nature is incomplete，there’s no shortage of fossil evidence to link the planet’s varied life forms into a great tree of life， a chart that scientists call a phylogenetic tree. You can think of humans as the very tip of just one branch on that tree called “hominid.” Chimpanzees exist at the end of an adjoining branch called “panin.” Follow both the hominid and panin branch back about 5.4 million years， and you’ll find a point where scientists think the two converged from a single，common ancestor. Fossil evidence helps scientists to reconstruct these trees，but so do morphological and genetic studlies. Genetic analysis has yielded striking similarities between chimps and humans. As such， scientists know a last common ancestor of chimps and humans existed，even if we’ve yet to determine the exact species. Yet paleoanthropologists have found numerous hominid fossils to bridge the evolutionary progression from that unknown common ancestor to modern humans. These finds include such famous East African fossils as Lucy（Australopithecus afarensis），which strengthened the importance of bipedalism in human evolution and proved an essential milestone on our way to modern Homo sapiens. Fossil evidence for human evolution will never be complete，as fossils themselves are rare geologic occurrences.Nevertheless，by incorporating other scientific disciplines，we’re able to build an increasingly accurate picture of just what our evolutionary family tree consisted of. What can be inferred from Para.5?A.Morpholoical and genetic studies helped scientists to trace unknown common ancestor of chimps and humans existed. B.Morphological and genetic studies determined exact species of common ancestor of chimps and humans existed. C.Genetic studies found hominid fossils to bridge the evolutionary progression from unknown common ancestor to modern humans. D.Morphological studies helped finding the famous East African fossils and set up an milestone in this field.

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考题共用题干 Natural MedicinesSince earliest days,humans have used some kinds of medicines.We know this because humans have survived.Ancient treatments for injury and disease were successful enough to keep humans from dying out completely.They were successful long before the time of modern medicine. Before the time of doctors with white coats and shiny（发亮的）instruments. Before the time of big hospitals with strange and wonderful equipment.Many parts of the world still do not have university-educated doctors. Nor do they have expensive hospitals.Yet injuries are treated.And diseases are often cured.How?By ancient methods. By medicines that might seem mysterious , even magical（有魔力的）.Traditional medicines are neither mysterious nor magical,however.Through the centuries , tribal（部落的）medicine men experimented with plants. They found many useful chemicals in the plants.And scientists believe many of these traditional medicines may provide the cure for some of today's most serious diseases.Experts say almost 80% of the people in the world use plants for health care.These natural medicines are used not just because people have no other form of treatment. They are used because people trust them. In developed areas,few people think about the source of the medicines they buy in a store .Yet many widely-used medicines are from ancient sources,especially plants.Some experts say more than 25%of modem medicines come,in one way or another,from nature.Scientists have long known that nature is really a chemical factory. All living things contain chemicals that help them survive .So scientists' interest in traditional medicine is not new.But it has become an urgent concern.This is because the earth's supply of natural medicines may be dropping rapidly. It is believed by scientists that traditional medicines______.A: can cure all kinds of diseasesB: may cure some of today's most serious diseasesC: are no longer useful for modern menD: are too cheap to be useful

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考题共用题干 Natural MedicinesSince earliest days,humans have used some kinds of medicines.We know this because humans have survived.Ancient treatments for injury and disease were successful enough to keep humans from dying out completely.They were successful long before the time of modern medicine. Before the time of doctors with white coats and shiny（发亮的）instruments. Before the time of big hospitals with strange and wonderful equipment.Many parts of the world still do not have university-educated doctors. Nor do they have expensive hospitals.Yet injuries are treated.And diseases are often cured.How?By ancient methods. By medicines that might seem mysterious , even magical（有魔力的）.Traditional medicines are neither mysterious nor magical,however.Through the centuries , tribal（部落的）medicine men experimented with plants. They found many useful chemicals in the plants.And scientists believe many of these traditional medicines may provide the cure for some of today's most serious diseases.Experts say almost 80% of the people in the world use plants for health care.These natural medicines are used not just because people have no other form of treatment. They are used because people trust them. In developed areas,few people think about the source of the medicines they buy in a store .Yet many widely-used medicines are from ancient sources,especially plants.Some experts say more than 25%of modem medicines come,in one way or another,from nature.Scientists have long known that nature is really a chemical factory. All living things contain chemicals that help them survive .So scientists' interest in traditional medicine is not new.But it has become an urgent concern.This is because the earth's supply of natural medicines may be dropping rapidly. It can be seen from the passage that the earth's supply of natural medicines______.A: may never be exhaustedB: may be dropping rapidlyC: is surprisingly bigD: is as rich as ever

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考题共用题干 Natural MedicinesSince earliest days,humans have used some kinds of medicines.We know this because humans have survived.Ancient treatments for injury and disease were successful enough to keep humans from dying out completely.They were successful long before the time of modern medicine. Before the time of doctors with white coats and shiny（发亮的）instruments. Before the time of big hospitals with strange and wonderful equipment.Many parts of the world still do not have university-educated doctors. Nor do they have expensive hospitals.Yet injuries are treated.And diseases are often cured.How?By ancient methods. By medicines that might seem mysterious , even magical（有魔力的）.Traditional medicines are neither mysterious nor magical,however.Through the centuries , tribal（部落的）medicine men experimented with plants. They found many useful chemicals in the plants.And scientists believe many of these traditional medicines may provide the cure for some of today's most serious diseases.Experts say almost 80% of the people in the world use plants for health care.These natural medicines are used not just because people have no other form of treatment. They are used because people trust them. In developed areas,few people think about the source of the medicines they buy in a store .Yet many widely-used medicines are from ancient sources,especially plants.Some experts say more than 25%of modem medicines come,in one way or another,from nature.Scientists have long known that nature is really a chemical factory. All living things contain chemicals that help them survive .So scientists' interest in traditional medicine is not new.But it has become an urgent concern.This is because the earth's supply of natural medicines may be dropping rapidly. The passage indicates that ancient treatments for injury and disease wereA: much more successful than modem onesB: successful enough for humans to surviveC: successful in all casesD: of little help to humans

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考题共用题干 Natural MedicinesSince earliest days,humans have used some kinds of medicines.We know this because humans have survived.Ancient treatments for injury and disease were successful enough to keep humans from dying out completely.They were successful long before the time of modern medicine. Before the time of doctors with white coats and shiny（发亮的）instruments. Before the time of big hospitals with strange and wonderful equipment.Many parts of the world still do not have university-educated doctors. Nor do they have expensive hospitals.Yet injuries are treated.And diseases are often cured.How?By ancient methods. By medicines that might seem mysterious , even magical（有魔力的）.Traditional medicines are neither mysterious nor magical,however.Through the centuries , tribal（部落的）medicine men experimented with plants. They found many useful chemicals in the plants.And scientists believe many of these traditional medicines may provide the cure for some of today's most serious diseases.Experts say almost 80% of the people in the world use plants for health care.These natural medicines are used not just because people have no other form of treatment. They are used because people trust them. In developed areas,few people think about the source of the medicines they buy in a store .Yet many widely-used medicines are from ancient sources,especially plants.Some experts say more than 25%of modem medicines come,in one way or another,from nature.Scientists have long known that nature is really a chemical factory. All living things contain chemicals that help them survive .So scientists' interest in traditional medicine is not new.But it has become an urgent concern.This is because the earth's supply of natural medicines may be dropping rapidly. What do the majority of the people in the world use for health care?A: Strange and wonderful equipment.B: Factory-produced chemicals.C: Modern medicines.D: Plants.

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考题共用题干 Natural MedicinesSince earliest days,humans have used some kinds of medicines.We know this because humans have survived.Ancient treatments for injury and disease were successful enough to keep humans from dying out completely.They were successful long before the time of modern medicine. Before the time of doctors with white coats and shiny（发亮的）instruments. Before the time of big hospitals with strange and wonderful equipment.Many parts of the world still do not have university-educated doctors. Nor do they have expensive hospitals.Yet injuries are treated.And diseases are often cured.How?By ancient methods. By medicines that might seem mysterious , even magical（有魔力的）.Traditional medicines are neither mysterious nor magical,however.Through the centuries , tribal（部落的）medicine men experimented with plants. They found many useful chemicals in the plants.And scientists believe many of these traditional medicines may provide the cure for some of today's most serious diseases.Experts say almost 80% of the people in the world use plants for health care.These natural medicines are used not just because people have no other form of treatment. They are used because people trust them. In developed areas,few people think about the source of the medicines they buy in a store .Yet many widely-used medicines are from ancient sources,especially plants.Some experts say more than 25%of modem medicines come,in one way or another,from nature.Scientists have long known that nature is really a chemical factory. All living things contain chemicals that help them survive .So scientists' interest in traditional medicine is not new.But it has become an urgent concern.This is because the earth's supply of natural medicines may be dropping rapidly. Which of the following statements is NOT true?A: Modern medicines are now available all over the world.B: Many big and modern hospitals are expensive.C: Traditional medicines are neither mysterious nor magical.D: Humans have used some kinds of medicines since earliest days.

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考题单选题We may infer from the second paragraph that ______.A gas price has no influence on drivers.B Toyota Yaris is not welcome in Manhattan.C Nissan Versa has already been well selling for its six-speed transmission.D Honda Fit is more economical than Chevy Suburban SUV.

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考题单选题We may infer from the fourth paragraph that ______.A humans have been growing food crops more than ten thousand years.B humans have learned how to produce biofuels for a long time.C humans are just on the beginning of making biofuels.D a cell wall includes four hemicellulose.

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考题单选题We can infer from the passage_______.A the ice can easily just slip into the oceanB volcanoes caused the ice to meltC melting just in the Northern hemisphere would have been impossibleD researchers often use the computer models help their research work

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考题问答题Animal rights are a controversial topic right now. Actually, the debate is focused mainly on animal testing. The following are opinions from both sides. Read the excerpts carefully and write your response in about 300 words, in which you should:　　1. summarize briefly the opinions from both sides, and then　　2. give your comment.　　Marks will be awarded for content relevance, content sufficiency, organization and language quality. Failure to follow the above instructions may result in a loss of marks.　　Animals are used for research in a variety of settings, including tests to determine the safety of drugs, cosmetics and other substances. Whether or not humans should use animals for testing purposes, however, is a controversial subject.　　Dr. Bob Miller, a medical researcher from Michigan State University, states that one of the primary advantages of animal testing is that it allows researchers to develop new medications and treatments, advancing the field of medicine and enhancing the health of society. For instance, many drugs used to treat or prevent cancer, HIV, diabetes, infections and other medical maladies have resulted from tests performed on animals.　　Moreover, animal testing enables scientists and researchers to test the safety of medications and other substances with which humans have regular contact. Drugs, for instance, may pose significant risks to humans, so testing them on animals fast gives researchers a chance to determine drugs’ safety before human trials are performed. While scientists are cognizant of the differences between humans and animals, the similarities are considered significant enough to produce relevant, useful data that they can then apply to humans. Thus, animal testing reduces harm to humans and saves lives.　　However, Prof. Abhay Shina, a leading critic of animal testing, points out that the major disadvantage to animal testing is that a significant number of animals are harmed or die as a result of experiments and testing. Unfortunately, many of the substances used on animal subjects never receive approval for human use or consumption. Humans receive no direct benefits as a result of the deaths of these animals. He also argues that animals are dissimilar enough from humans to make the results of animal tests unreliable. A related criticism is that testing induces stress in the animals, meaning that the subjects do not react to experimental substances in the same way that they might in more natural circumstances, making the results of experiments less valid.　　Using animals as research subjects is also expensive, because the animals require food, shelter, care and treatment in addition to the costs of experimental substances. Long-term or multi-phase tests can increase the costs of the practice as well. The actual price paid for the animals is also worth consideration; there are companies that breed and sell animals specifically for testing purposes.

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考题问答题Green Gene Technology　　For the past 10,000 years humans have influenced the plants they use at first unknowingly, later by design. Today’s crops have been created by a process of selection and classical breeding. More specific improvements in breeding will be possible in future.　　Science has cracked the genetic information code. Green gene technology is an effective tool in crop breeding, enabling us to develop new crops even more rapidly and specifically. We can make them more efficient, optimizing their contents and valuable substances to suit the wishes and requirements of customers and the processing industry. Their metabolism can be individually modified, making them produce starch, protein and fats with special properties. Through gene transfer plants can be made more resistant to viruses, bacteria, harmful fungi and insect pests.　　Genetically modified plants can be cultivated to possess improved stress behavior, with the result that they absorb water better in dry locations and can make more efficient use of soil nutrients. We can also optimize weed control. To do so, we make crops tolerant to environmentally sound and easily degradable herbicides. This is not as simple as it sounds. But we have been successful: Innovator has been on the Canadian market since 1995. This is the first oilseed rape variety to contain the glufosinate tolerance gene, facilitating the use of AgrEvo’s broad-spectrum herbicide liberty.　　We are committed to green gene technology, with which we aim to make crop breeding even more efficient and environmentally friendly. Before being brought on to the market these genetically modified plants are researched and tested for years until the questions posed regarding their safety have been answered. This is a great opportunity for us to realize our vision: the use of faster methods to breed varieties which will continue to provide us with sufficient food and raw materials in future. Our fossil reserves will soon be exhausted. Experts estimate that we only have enough oil for another 43 years and natural gas for less than 60.　　This means we must rethink and act accordingly, using new crop varieties to step up the move to replenishable sources of raw materials and energy. In other words, green gene technology is the key technology for sustainable agriculture.

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