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科目:高中英語 來源:同步題 題型:閱讀理解
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科目:高中英語 來源:同步題 題型:閱讀理解
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科目:高中英語 來源:同步題 題型:閱讀理解
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科目:高中英語 來源:江西省同步題 題型:閱讀理解
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科目:高中英語 來源:廣東省期末題 題型:閱讀理解
Judging from recent surveys, most experts in sleep behaviour agree that there is an epidemic (流行病) of sleepiness in the nation. “I can’t think of a single study that hasn’t found Americans getting less sleep
than they ought to,” says Dr. David. Even people who think they are sleeping enough would probably be
better off with more rest.
The beginning of our sleep-lack crises can be traced back to the invention of the light bulb a century
ago. From diary entries and our personal accounts from the 18th and 19th centuries, sleep scientists have
reached the conclusion that the average person used to sleep about 9.5 hours a night. “The best sleep
habits once were forced on us, when we had nothing to do in the evening on the farm, and it was dark.” By the 1950s and 1960s, the sleep schedule had been reduced dramatically, to between 7.5 and 8 hours, and most people had to wake to an alarm clock. “People cheat in their sleep, and they don’t even realize
they’re doing it,” says Dr. David. “They think they’re okay because they can manage with 6.5 hours, when they really need 7.5, 8 or even more to feel ideally energetic.”
Perhaps the most cruel robber of sleep, researches say, is the complexity of the day. Whenever
pressures from work, family, friends and community increase, many people consider sleep the least
expensive item on their programme. “In our society, you’re considered energetic if you say you need only 5.5 hours’ sleep. If you have to get 8.5 hours, people think you lack drive and ambition.”
To determine the consequences of sleep-lack, researchers have put subjects through a set of
psychological and performance tests requiring them, for instance, to add columns of numbers or recall a
passage read to them only minutes earlier. “We’ve found that if you’re lacking in sleep, performance
suffers,” says Dr. David. “Short-term memory is weakened, so are abilities to make decisions and to
concentrate.”
1. What is the main topic of the passage?
A. Research on the causes and consequences of sleep-lack.
B. The epidemic of sleepiness in the modern times.
C. The history of people’s sleeping patterns.
D. The minimum of our sleeping hours.
2. Which of the following is Dr. David’s opinion?
A. People who think they are sleeping enough are better off than those who don’t.
B. Some people can remain energetic with only 6.5 hours’ sleep a night.
C. If they get 8.5 hours’ sleep, people will be full of drive and ambition.
D. People’s performance becomes worse if they are lacking in sleep.
3. People in the 18th and 19th centuries slept about 9.5 hours a night because __________.
A. they were forced by their parents to do so
B. they knew what was best for their health
C. they had no electricity
D. they were not so energetic and ambitious as modern people are
4. The major cause of sleep-lack of modern people is _______.
A. the endless TV programmes in the evenings and on the Internet
B. the heavy work load of the day
C. the enough energy modern people usually have
D. loud noises in the modern cities
5. What does the word “subject” in paragraph 4 mean?
A. Person or thing that is being discussed or described.
B. Branch of knowledge studied in a school.
C. Person or thing being treated in a certain way or being experimented on.
D. Any member of a State apart from the supreme ruler.
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科目:高中英語 來源:同步題 題型:閱讀理解
閱讀理解
Batteries can power anything from small sensors to large systems.While scientists are finding ways to
make them smaller but even more powerful, problems can arise when these batteries are much larger
and heavier than the devices themselves.University of Missouri(MU) researchers are developing a
nuclear energy source that is smaller, lighter and more efficient.
“To provide enough power, we need certain methods with high energy density (密度) .”said
Jae Kwon,assistant professor of electrical and computer engineering at MU.“The radioisotope
(放射性同位素)battery can provide power density that is much higher than chemical batteries.”
Kwon and his research team have been working on building a small nuclear battery,presently the
size and thickness of a penny,intended to power various micro/nanoelectromechanical
systems(M/NEMS) .Although nuclear batteries can cause concerns,Kwon said they are safe.
“People hear the word‘nuclear'and think of something very dangerous.”he said.“However, nuclear
power sources have already been safely powering a variety of devices, such as pacemakers,space
satellites and underwater systems.”
His new idea is not only in the battery's size, but also in its semiconductor(半導(dǎo)體) .Kwon's battery
uses a liquid semiconductor rather than a solid semiconductor.
“The key part of using a radioactive battery is that when you harvest the energy, part of the radiation
energy can damage the lattice structure(晶體結(jié)構(gòu))of the solid semiconductor.”Kwon said.“By using a
liquid semiconductor, we believe we can minimize that problem.”
Together with J .David Robertson, chemistry professor and associate director of the MU Research
Reactor, Kwon is working to build and test the battery.In the future, they hope to increase the battery's
power,shrink its size and try with various other materials.Kwon said that the battery could be thinner
than the thickness of human hair.
1 .Which of the following is true of Jae Kwon?________
A. He teaches chemistry at MU.
B .He developed a chemical battery.
C .He is working on a nuclear energy source.
D .He made a breakthrough in computer engineering.
2 .Jae Kwon gave examples in Paragraph 4________.
A .to show chemical batteries are widely applied
B .to indicate nuclear batteries can be safely used
C .to describe a nuclearpowered system
D .to introduce various energy sources
3 .Liquid semiconductor is used to________.
A .get rid of the radioactive waste
B .test the power of nuclear batteries
C .decrease the size of nuclear batteries
D .reduce the damage to lattice structure
4 .According to Jae Kwon,his nuclear battery________.
A .uses a solid semiconductor
B .will soon replace the present ones
C .could be extremely thin
D .has passed the final test
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科目:高中英語 來源:0123 月考題 題型:閱讀理解
At 2:30 December 5, 1945, five US Navy training planes took off in clear weather from the base Lauderdale, Florida. The planes flew east over the coast… and disappeared. The group was Flight 19, on a run between
Florida and Bahamas. Tailor was the group leader. At about 3:40, Tailor reported that his compasses (指南針)
were not reading properly. The other planes followed their leaders aimlessly, first east, then west, then
northeast over the ocean, as Tailor tried to make sure of the direction by radio. Then, suddenly Tailor was
heard to give orders to dive…
Quickly, two giant Martin seaplanes were sent up to search for Flight 19. Several hours later, the wind
became strong and visibility (能見度) dropped. A return to base was ordered. But only one of the Martin
seaplanes landed. Four days later, the Navy and Coast Guard combed a 100,000 square-mile area with more
than 100 planes and ships. No sign was ever shown of the missing planes.
Today, people have noted the disappearance of many ships and planes in the southwest part of the North
Atlantic and began to call this area the Bermuda Triangle.
The points of the triangle are Bermuda, Puerto Rico and a particular place in the Gulf of Mexico, west of
Florida. It is a two-faced water world of tiny islands, bright beaches and beautiful waters. Yet thick fogs,
powerful currents (激流) and sudden storms are hidden behind this smiling surface.
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科目:高中英語 來源:模擬題 題型:閱讀理解
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