EVERYONE has those nights – you lie in your bed for hours, tossing and turning, totally unable to fall asleep. You wish you could just turn your brain off as if it were a light. That would make things much easier, wouldn’t it?
Now it looks like you are one step closer to this wild dream of yours – scientists from Oxford University, UK have just discovered the “switch” that tells the brain to go to sleep, reported Forbes.
To understand the study, you first need to know that there are two mechanisms (機(jī)能) that regulate sleep. There’s one that we’re already familiar with – our body clock, which works in a 24-hour cycle based on the light changes throughout the day.
The other one is what scientists call the sleep “homeostat (動態(tài)平衡系統(tǒng))”. This mechanism has nothing to do with daylight. Instead, it keeps track of the brain’s waking hours and urges it to rest if it has been awake for a long time. “It is similar to the thermostat (自動調(diào)溫器) in your home. A thermostat measures temperature and switches on the heating if it’s too cold,” Professor Gero Miesenböck, who led the study, told The Telegraph.
Our bodies use both of the mechanisms to regulate sleep. “The body clock says it’s the right time, and the sleep thermostat has built up pressure during a long waking day,” explained Miesenböck.
There is no way that scientists can trick the body clock. But with the sleep homeostat, there might be something they can do.
The researchers found that the sleep homeostat works by activating a specific group of nerve cells, or neurons, in the brain. They tested their theory on fruit flies by removing the neurons from the insects’ brains. And as expected, they found that the flies without the homeostat neurons did not keep a regular sleep pattern anymore.
Now that scientists have pinpointed (定位) the exact place in the brain – or, the “switch” – that regulates sleep, they can begin investigating (研究) how to activate these cells at any given time so that people can be sent to sleep instantly.
More importantly, figuring out how sleep mechanisms work may also help us to one day unravel one of the oldest mysteries of all: why do we need to sleep in the first place?
小題1:What is the article mainly about?
A．A new way to treat sleep disorders.
B．The discovery of the sleep “homeostat”.
C．Advice on what to do when you fail to fall asleep.
D．A comparison of the two mechanisms that regulate sleep.
小題2:How does the author explain the function of the sleep homeostat?
A．Through examples.
B．With comparisons.
C．Through cause and effect analysis.
D．By presenting research findings.
小題3:What can we conclude from the article?
A．Generally, the sleep homeostat has less effect on people during the day than at night.
B．There is little scientists can do to affect the way the sleep homeostat works.
C．What makes us go to sleep at night is probably a combination of the two mechanisms.
D．The more homeostat neurons there are in one’s brain, the more easily one can fall asleep.
小題4:The underlined word “unravel” in the last paragraph is closest in meaning to ______.
A．put up withB．figure outC．keep track ofD．take notice of

小題1:B
小題2:B
小題3:C
小題4:B

試題分析：很多人有失眠的經(jīng)歷，那么大腦中有“睡眠開關(guān)”嗎？科學(xué)家最近發(fā)現(xiàn)影響睡眠的除了生物鐘，還有一種睡眠動態(tài)平衡系統(tǒng)，我們晚上睡覺的是兩個技能的結(jié)合，科學(xué)家正在研究怎樣通過睡眠動態(tài)平衡系統(tǒng)來改善我們的睡眠。
小題1:主旨題：根據(jù)第四段的句子：The other one is what scientists call the sleep “homeostat (動態(tài)平衡系統(tǒng))”. This mechanism has nothing to do with daylight. Instead, it keeps track of the brain’s waking hours and urges it to rest if it has been awake for a long time.可知這篇文章講的是睡眠動態(tài)平衡系統(tǒng)的發(fā)現(xiàn)，選B。
小題2:寫作手法題：根據(jù)第四段的內(nèi)容：可知作者解釋睡眠動態(tài)平衡系統(tǒng)的的功能是通過和生物鐘對比。選B
小題3:細(xì)節(jié)題：從第五段的句子：Our bodies use both of the mechanisms to regulate sleep. “The body clock says it’s the right time, and the sleep thermostat has built up pressure during a long waking day,” explained Miesenböck.可知讓我們晚上睡覺的是兩個技能的結(jié)合，選C
小題4:猜詞題：根據(jù)最后一段的句子：More importantly, figuring out how sleep mechanisms work may also help us to one day可知“unravel”的意思和前面的figure out相似，是“弄明白”，選B。
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科目：高中英語 來源：不詳 題型：閱讀理解

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B．How to Keep Ecological Balance
C．Effects of Forest Fires
D．Methods of Fire Spread Control
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B．prevent the forest fire from occurring
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科目：高中英語 來源：不詳 題型：閱讀理解

As we enjoy the summer ocean waves along the beaches, we may think nervously about Steven Spielberg's Jaws and the great fear that sharks inspire in us. Yet we are happy to see global efforts to protect the declining number of sharks. The world has realized that we need the species, like sharks, to keep a balanced ecosystem.
Sharks, in particular, are “in” these days. Thanks to good public policy and famous stars such as Jackie Chan and Ang Lee, killing sharks for fin soup is no longer cool.
The demand for shark fins has been rising for decades, threatening sharks with extinction(滅絕)—up to 100 million sharks are killed each year just for their fins. But we have started to reverse the trend, particularly in many areas of the United States and overseas where restaurants once proudly provided delicious shark fins on the menu.
In California, a ban on the sale and possession of shark fin soup has gone into effect this year through the efforts of Wild Aid and other organizations.
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B．keep his house safe
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C．a(chǎn)vailable for common people
D．suitable to wear on the wrist
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B．The wristband will get false information of a person.
C．It will not be used in the proper way.
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科目：高中英語 來源：不詳 題型：閱讀理解

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科目：高中英語 來源：不詳 題型：閱讀理解

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The decision has aroused a heated discussion among Shanghai educators and parents who doubted the reform would re­duce the burden of learning English or if the substitute test could reflect a student’s English skills and help students learn English better.
“The reform shows China is learning from the West to give students more test-taking chances. But more chances might become more of a burden since Chinese students are likely to repeat the test until they get the highest score,” said Cai Jigang, a professor at Fudan University’s College of Foreign Languages and Literature and chairman of the Shanghai Advisory Committee for College English Teaching at Tertiary Level.
Yu Lizhong, chancellor of New York University Shanghai, where classes are in English and students are required to have a high standard of English, said the most important aspect of the reform lay in what to test and how to test.
“ As far as I see, the reform doesn’t mean English is no longer important for Chinese students after it will be excluded from the unified college entrance exam,” Yu said. “In a way, English is even more important than before since the test would only serve as reference, while every college and university, even every major, can have different requirements of a student’s English skills under a diverse evaluation system. ”
Yu said some students will have their study pressure reduced if the major they choose doesn’t need excellent English while others still need to study hard if they want to be among the best students.
The education ministry said the reform would not affect students attending the college entrance exam over the next three years.
小題1:What can we learn from the first paragraph?
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B．It has been 30 years since English became one subject of national college entrance exam.
C．China’s once-in-a-lifetime exam system is unacceptable at all.
D．The system that tests are held several times does more good than once-in-a-lifetime exam system.
小題2:According to the passage, Shanghai educators and parents argue that _____.
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B．English shouldn’t be removed from China’s college entrance exam
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小題3:What does the passage try to express in the underlined sentence?
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A．To advise students not to devote themselves to English.
B．To call on Education Department to remove English from “Gaokao”.
C．To support the act of Ministry of Education.
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科目：高中英語 來源：不詳 題型：閱讀理解

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B．Cars that run on thin air.
C．Formula One racing car designer.
D．Dependence on foreign oil.
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B．The name of a balloon.
C．The name of a car company.
D．The name of a car designer.
小題3:The underlined world “Confining” in Paragraph 4 can be replaced by ___________.
A．KeepingB．PreventingC．PushingD．Running
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A．How much pressure the air creates.
B．How the car works.
C．What the normal air pressure is.
D．How the air gets into the engine.

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科目：高中英語 來源：不詳 題型：完形填空

It is nice to know what the weather will be like when we plan a trip. Do you know anything about the history of weather? Don’t look at the sky. Don’t look for old weather reports. Looking at the tree rings is more important. Correct weather reports date back only one century, but some trees can provide an exact record of weather even further back.
It is natural that a tree would grow best in a climate with plenty of sunlight and rainfall. It is also expected that little sunlight or rainfall would reduce the growth of a tree. The change from a favorable to an unfavorable climate can be found out by the reading pattern of rings in a tree trunk. To find out the weather of ten years ago, you can count the rings of a tree trunk from the outside to the inside. If the tenth ring is far from the other rings, then it is certain that plenty of sunny and rainy weather occurred. If the rings are close together, then the climate was bad for the tree.
Studying trees is important not only for the history of weather, but also for the history of man. In an area of New Mexico you can find only sand — no trees or people. However, many centuries ago a large population lived there. They left suddenly. Why?
A scientist studied the pattern of the rings of dead trees that had grown there. He made up his mind that the people had to leave because they had cut down all the trees. Trees were necessary to make fires and buildings. So, after the people destroyed the trees, they had to move.
In this example studying tree rings uncovered an exciting fact about the history of man.
小題1:We can find out the weather of five years ago by counting the rings of a tree trunk ____.
A．from the left to the right
B．from the right to the left
C．from the inside to the outside
D．from the outside to the inside
小題2:If the ring was far from the others, we can conclude that the weather of that year was ______.
A．badB．sunnyC．favorableD．rainy
小題3:By studying the rings of dead trees in an area of New Mexico, the scientist found _______.
A．why the people had to leave
B．where the people had to go
C．what the people had to eat
D．how the people left
小題4:The ancient people usually lived where there were plenty of trees mainly because ______.
A．trees provided an exact record of weather for research
B．trees could supply them with fruit and food to live on
C．trees could supply them with shades
D．trees were materials for fires and buildings
小題5:By giving the example of an area of New Mexico, the author tries to prove        .
A．trees can’t live in the area without population
B．that studying trees is important for the history of man and weather.
C．what the real relation is between tree rings and the history of man and weather
D．the history of man is important for the history of trees

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科目：高中英語 來源：不詳 題型：閱讀理解

Is the ‘Go to College’ Message Overdone?
Even in a weak job market, the old college try isn’t the answer for everyone. A briefing paper from the Brookings Institution warns that “we may have overdone the message” on college, senior fellow Isabel Sawhill said.
“We’ve been telling students and their families for years that college is the only way to succeed in the economy and of course there’s a lot of truth to that,” Ms. Sawhill said. “On average it does pay off… But if you load up on a whole lot of student debt and then you don’t graduate, that is a very bad situation.”
One comment that people often repeat among the years of slow job growth has been the value of education for landing a job and advancing in a career. April’s national unemployment rate stood at 7.5%, according to the Labor Department. The unemployment rate for high-school graduates over 25 years old who hadn’t attended college was 7.4%, compared with 3.9% for those with a bachelor’s degree or more education. The difference is even bigger among those aged 16-24. The jobless rate for those with only a high school diploma in that age group is about 20%. At the same time, recent research by Canadian economists cautions that a college degree is no guarantee of promising employment.
Ms. Sawhill pointed out that among the aspects that affect the value of a college education is the field of one’s major: Students in engineering or other sciences end up earning more than ones who major in the arts or education. The cost of tuition and the availability of financial aid are other considerations, with public institutions generally a better financial bargain than private ones.
She suggested two avenues for improving the situation: increasing vocational(職業(yè)的)-technical training programs and taking a page from Europe’s focus on early education rather than post-secondary learning. “The European countries put a little more attention to getting people prepared in the primary grades,” she said. “Then they have a higher bar for whoever goes to college—but once you get into college, you’re more likely to be highly subsidized(資助).”
She also is a supporter of technical training—to teach students how to be plumbers, welders and computer programmers—because “employers are desperate” for workers with these skills.
小題1:People usually think that _____.
A．the cost of technical schooling is a problem
B．one will not succeed without a college degree
C．technical skills are most important for landing a job
D．there is an increased competition in getting into a college
小題2:What does the underlined part “taking a page from” mean?
A．Hearing from.B．Changing from.
C．Differing from.D．Learning from.
小題3:What can we infer from the passage?
A．Public institutions charge more for education.
B．European universities are stricter with students.
C．Students with certain skills are in great demand.
D．Canadian students prefer to major in engineering.
小題4:Ms. Sawhill may probably agree that _____.
A．too much stress has been put on the value of college degrees
B．technical training is more important than college education
C．a(chǎn) college degree will ensure promising employment
D．it’s easier for art students to find favorite jobs

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