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I have not found my stowage plan yet; in fact，I am not sure（）I could have done with it.
A . whether
B . what
C . why
D . whe
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Since many insects have already become（）to DDT, scientists have to look for some new insecticide
A、active
B、resistant
C、tough
D、gradual
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Over（）science parks have been set up by higher education institutions in conjunction with industrial scientists and technologists.
A . 10
B . 20
C . 30
D . 40
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I have found myself ( ) great interest in spoken English.
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Scientists have to _______ past experiences in making new ideas.
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we have shipped the replacement for all the items you have found______.
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According to the passage, scientists have discovered that influenza viruses_____.
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Scientists have invented a robot which can cook for people. Nowadays, science and technology______ every aspect of our lives.
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Have scientists found of water on Mars?
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________ the calculation is right， scientists can never be sure that they have included all variables and modeled them accurately.
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Modern scientists ______ that truth is not something that we assume, but something found at the end of long investigations.
A．affirm
B．confirm
C．suppose
D．presume
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Scientists have ______ for years that turbulence within the gaseous clouds found throughout the Milky Way stymies star formation, but some of the forces behind this disturbance remain ______ .
A．doubted... insufferable
B．posited... unknown
C．argued... relative
D．assumed... exoteric
E．conveyed ... insuperable
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As some scientists have found, the vigorous exercise can make nerve cells to form. interconnected webs that make the brain run ______.
A．steadily and more effectively
B．faster and more efficiently
C．more powerfully
D．more effectively
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听力原文： Scientists say sharks have lived in the world's oceans for millions of years. Scientists say there are more than 350 different kinds of sharks.
Sharks do not have bones, and a shark has an extremely good sense of smell. It can find. small amounts of substances in the water, such as blood, body liquids and chemicals produced by animals. Sharks also sense electrical and magnetic power linked to nerves and muscles of living animals. These powerful senses help them find their fond. Some sharks will eat just about anything. Many unusual things have been found in the stomachs of some large sharks. They include shoes, dogs, a cow's foot and metal protective clothing.
About forty percent of the different kinds of sharks lay eggs. The others give birth to live young. Some sharks carry their young inside their bodies like humans do.
Scientists are beginning to understand the importance of sharks to humans. Medical researchers want to learn more about the shark's body defense system against disease. They know that sharks recover quickly from injuries. Sharks appear never to suffer infections, cancer or heart diseases.
What is this passage mainly about？
A．The necessity of protecting sharks.
B．The living environment of sharks.
C．The dangers of sharks to human beings.
D．An introduction to sharks.
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Scientists have discovered a genetic defect that a...
Scientists have discovered a genetic defect that appears to cause deficit-hyperactivity disorder, more commonly known as hyperactivity. People afflicted with this disorder have trouble focusing their attention and controlling impulses, and tend to be rest-less and aggressive. The defect occurs in a gene that regulates the body's use of the thyroid hormone. This finding was made in continuing study organized by the National Institute of Diabetes and Digestive and Kidney Diseases in which 70 percent of children inheriting the gene were hyperactive while only 20 percent of the children not inheriting the gene were hyperactive. And although the researchers admit that this defective gene probably accounts for only a fraction of cases of hyperactivity, this discovery will allow doctors to spot newborn babies likely to have the disorder, and also to provide clues for its cause and treatment.
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Scientists have discovered a close_____between smoking and several serious diseases.
A．action
B．connection
C．union
D．function
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Within ten years scientists will probably have___________.
A．the nucleus of a cell
B．cloned human beings
C．a human being in two years
D．a law to ban human cloning
E．a report on hunman cloning
F．heavy media coverage
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Scientists put forward that Northern Europe would have __________ if climate continues, while Britain would have warmer weather。
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Where Have All the Bees Gone？Scientists who study insects have a real mystery on their hands．A11acro...<br/>What is the mystery that researchers find hard to explain?（）
A．Honeybees are flying all across the country.
B．25-40 percent of the honeybees in the US have died.
C．Honeybees are leaving their hives and do not return.
D．Honeybee hives are in disorder．
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Scientists have known how to h______ (治理，利用) the limitless power of the sun.
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Scientists have long believed one way to stop the Earth’s atmosphere from warming is by planting more trees. The idea is that more trees will take in or absorb some of the carbon dioxide in the atmosphere. Carbon dioxide is a gas released by cars, factories and other human activities. The gas traps heat in the Earth’s atmosphere, which warms the planet. However, two new studies have found that trees may not be as helpful in reducing carbon dioxide as had been thought.
The first study was done at Duke University in Durham, North Carolina. Researchers pumped extra carbon dioxide into a test area where pine trees were growing. The trees grew thirty-four percent faster during the first three years. However, in time, the trees slowed to about their normal growth rate. The scientists say this is because trees need other nutrients, such as nitrogen.
In the second study, researchers from Duke and Bowdoin College in Brunswick, Maine examined the soil around trees. They discovered that as the leaves broke down into the soil, all the carbon was not trapped in the soil. Much of it was released into the atmosphere as carbon dioxide.
The findings of the two studies were published last month in Nature magazine. They suggest there is limited value in planting trees to reduce the carbon dioxide pollution in the atmosphere.
Forest planting has been a part of negotiations on a world agreement to reduce greenhouse gases that scientists believe cause global warming. The United States, Canada, Japan and some other industrial countries have supported the idea. But this new research suggests the idea is not as effective as environmental activists had thought. Scientist Ram Oren of Duke University led the study on tree growth. He says that earlier estimates on the ability of forests to absorb carbon dioxide were overly hopeful.
Some scientists not involved in the studies say the research provides some of the first evidence on how trees react to carbon dioxide. Other scientists say the research disputes a belief among some coal and power companies. The companies say that rising levels of carbon dioxide in the atmosphere will not create harmful global warming. Instead, they say it will increase forests and other plants.
What is the purpose of this passage？
A．Introduce some new ideas about the relationship between trees and carbon dioxide.
B．Introduce recent condition of global industrial pollution.
C．Call on people to plant more trees to reduce greenhouse gases.
D．Point out that power companies should be responsible for the rising levels of carbon dioxide.
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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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Many scientists have been probingpsychological problems（）
A．solving
B．exploring
C．settling
D．handling
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Our factory have founded in 1987.（请将存在语法和或结构错误的部分找出来。)
