题目内容
（请给出正确答案）
Now scientists know ______.
A．what makes people feel cool near a lake or a river in summer
B．everything about the ocean
C．why the ocean does not get more and more salty
D．what happens to the salt in the ocean
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In 1934 the scientist William Beebe dived 3 , 000 feet below the surface in a hollow steel ball. In 1935 Auguste Piccard dived 10, 330 feet. In 1960 his son Jean dived to a【35】of 35, 800 feet.
All these early dives were deep. But the divers could not stay down for very long. They had to【36】the surface after a few seconds. Scientists needed to stay down longer to study life below the surface.【37】, they succeeded. Cousteau, a Frenchman, was able to【38】down to a depth of【36】feet for one month and to a depth of 90 feet for a week.
Now scientists are developing even【39】equipment. With this new equipment, men can stay【40】the surface for days or【41】weeks. In 1962 Consteau【42】a research station 35 feet below the surface. Then in 1964 he set up another station on the ocean floor of the Red Sea. This was the first undersea station to operate【43】help from the surface.
Many countries are now studying undersea【44】. The Soviet Union has an undersea laboratory in the Crimean Sea. The United States has a laboratory 50 feet【45】on the ocean floor【46】the Virgin Islands. In 1970 five men lived there for two weeks. Then a【47】of five women scientists stayed in the laboratory.【48】came other teams of men. All were there to explore the ocean depths and【49】plans for the use of its resources. Scientists hope to find enough【50】, vegetable, and animal wealth there to provide food for the whole world.
(31)
A．in
B．to
C．on
D．under
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. ”
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. ”
The source of the sun' s inconstancy is magnetism. Professor William Livingston has developed new theories about its magnetic nature.
"We don' t yet know what causes sun spots, "he says, "but we now think they ' re areas of high level magnetism that come up from the sun' s interior. So strong is their magnetic pull that the highly ionized gas nearby is not able to transmit energy out. "As a result these areas send out less heat and light and thus appear from Earth to be almost dark irregular surface patches.
Sun spot activity generally fluctuates in steady, 11-year cycled. Scientists have long formed the o pinion that as the size and number of sun spots increased, the overall energy sent out by the sun would de crease. Indeed, recent studies confirmed it, revealing that during peak periods of sun spot activity, the Earth experiences a small drop that can be seen clearly in received solar energy.
Could such a small drop in energy have an effect here on earth？ Perhaps some scientists think the world temperature could fall by' as much as 0.2 during periods of high solar magnetism.., enough to cause significant fluctuations in weather patterns.
According to the passage, it is believed that the sun ______ ．
A．moves in a quick but steady way year after year
B．sends out less and less heat and light with each passing year
C．radiates the same amount of light every year
D．might have a strong influence on the weather patterns
Surrounding the earth was an unbroken canopy of clouds miles thick and made up mostly of water vapor. Rain falling toward the still-hot earth was heated to steam and rose to the clouds again. After many millions of years, as the earth continued to cool, its surface temperature fell below the boiling point of water. Rainwater could now remain on the earth, covering its whole surface except for the higher places on earth that had been formed from the lighter rock materials.
In 1970, scientists had pieced together evidence that the lighter rock materials had formed one huge continent by a vast ocean. Then, about 200 million years ago, the great continent began to break up, the pieces moving slowly apart.
The onrushing waters of the single huge ocean now entered and filled the spaces between the separating continents--and became the several oceans and seas we know today.
This passage mainly talks about ______.
A．the origin of the earth
B．the origin of the ocean
C．the history of the earth
D．the forming of the earth's crust
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. ”
Does this sound familiar？ You have probably read something like it in magazines or books, or seen it in a film. Why is it so popular？ One of the reasons is that it reflects the fears of many people; fear of the unknown fear of what is not understood or, at least, fear of something that is not completely understood.
The fact is that every day it seems that computers take control of another area of our lives. Some
factory jobs are now done by robots and the robots are controlled by computers. Our bank accounts are managed by computers. At the airport, our tickets are sold by a computer. Certainly, many of these operations are made more
efficient by computers, but our admiration is sometimes mixed with unsafe feelings. And this lack of safety is caused by the fact that we do not know how computers do these things, and we really don't know what they might do next. But we can find out how computers work, and once we understand them, we can use computers instead of worrying about being used by them. Today, there is a new generation of computer wizards who know exactly how computers get things done. These young men and women, usually university students, are happy to sit for hours, sometimes for days, designing programs, not eating, not sleeping, but discovering what can be done by these wonderful slaves which they have learned to control. These computer wizards have learned to use the computer and search for new tasks for their machines.
(1)、According to the passage, our present world is under the control of ______ .
A：mad scientists
B：men and women
C：the unknown fear
D：some super-inventions
(2)、The reason why many people are afraid of computers is that ______ .
A：they don't know anything about computers
B：they haven't really understood computers
C：there are so many computer games
D：computers are often down
(3)、The author mentions computer wizards in order to point out that ______ .
A：computers can be controlled by man
B：there should be more people devoted to computers
C：only young people are interested in computers
D：more time and energy is required to control computers
(4)、This passage is probably written to suggest that ______ .
A：some day computers can deal with all human problems
B：computers can be used in place of traveling to our jobs
C：people should not fear computers
D：computer technology will not meet people's needs in various situations
(5)、The author's attitude towards widely used computers is __.
A：positive
B：anxious
C：worried
D：serious
Which of the following statements in true？
A．Women's struggle for recognition has been completely won.
B．Women have proved their abilities in many fields.
C．Women can not get the same educational opportunities as men.
D．Women are now regarded as equal to men all over the world.
Up to now scientists have not found how to ______ patients of that disease.
A．cure
B．treat
C．deal with
D．get rid of
Asteroids are different forms of the meteoroids that race across the night sky. Most orbits the sun far from Earth and don't threaten us. But there are also thousands of asteroids whose orbits put them on a violent coming course together with Earth.
Buy $ 50 million worth of new telescopes right now. Then spend $10 mil]ion a year for the next 25 years to locate most of the space rocks. By the time we spot a fatal one, the scientists say, we'll have a way to change its course.
Some scientists favor pushing asteroids off course with nuclear weapons. But the cost wouldn't be cheap.
Is it worth it？ Two things experts consider when judging any risk are: 1) How likely the event is; and 2) How bad the consequences if the event occurs. Experts think asteroids big enough to destroy lots of life might strike Earth once every 500,000 years. Sounds pretty rare but if one did fall it would be the end of the world. "If we don't take care of these big asteroids, they'll take care of us. "Says one scientist. "Its that simple."
The cure, though, might be worse than the disease, Do we really want fleets of nuclear weapons silting around on Earth？ "The world has less to fear from doomsday rocks than from a great nuclear fleet set against them. "Said a New York Times article.
What does the passage say about asteroids and meteoroids？
A．They are heavenly bodies similar in nature.
B．There are more asteroids than meteoroids.
C．They are heavenly bodies different in composition.
D．Asteroids are more mysterious than meteoroids.
