For grown-ups, an afternoon snooze (打盹) is often easier said than done. But many of us have probably experienced just how simple it can be to catch some sleep in a gently rocking hammock (吊床). By examining brain waves in sleeping adults, researchers reported in the June 21 issue of Current Biology, a Cell Press publication, that they now have evidence to explain why that is.
“It is a common belief that rocking causes sleep: we fall asleep in a rocking chair soon and, since ancient times, we cradle our babies to sleep,” said Sophie Schwartz of the University of Geneva. “Yet, how this works had remained a mystery. The goal of our study was made up of two parts: to test whether rocking does indeed improve sleep, and to understand how this might work at the brain level.”
Schwartz, Michel Mühlethaler, and their colleagues Laurence Bayer and Irina Constantinescu asked twelve adult volunteers to nap on a custommade bed or “experimental hammock” that could either remain still or rock gently. All participants were good sleepers who didn’t typically nap and did not suffer from excessive sleepiness during the day. Each participant took two 45•minute afternoon naps, one with the bed still and one with the bed in motion, while their brain activity was monitored.
“We observed a faster transition to sleep in each and every subject in the swinging condition,” Mühlethaler said. “Surprisingly, we also observed a dramatic boosting of certain types of sleeprelated brain waves.”
More specifically, rocking increased the length of stage N2 sleep, a form of non•rapid eye movement sleep that normally occupies about half of a good night’s sleep. The rocking bed also had a lasting effect on brain activity, increasing slow brain waves and bursts of activity known as sleep spindles (纺锤体).
Schwartz and Mühlethaler say the next step is to find out whether rocking can improve longer periods of sleep and to find out whether it may be useful for the treatment of sleep disorders, such as insomnia (失眠).
1.What does the June 21 issue of Current Biology tell us according to Paragraph 1?
A.It is more difficult for grown•ups to fall asleep.
B.People today like to sleep in a rocking hammock.
C.Many people nowadays suffer from excessive sleepiness.
D.There comes the evidence for why rocking benefits people’s sleep.
2.What can we learn from Sophie Schwartz’s words?
A.Her team aimed to answer two questions.
B.The study is going to benefit babies a lot.
C.The study had been kept secret before being finished.
D.People used to believe rocking was bad for sleep.
3.What finding was beyond the researchers’ expectation?
A.The rocking seemed to improve participants’ sleep quality.
B.All the participants fell asleep faster in the swinging condition.
C.Some participants couldn’t fall asleep in the swinging condition.
D.Participants had a tendency to sleep excessively in the swinging bed.
4.What is the best title?
A.Take a Snooze Easier Said than Done
B.Want a Faster Sleep? Change Your Sleeping Habits
C.Need a Nap? Find Yourself a Hammock
D.Suffer from Sleep Disorder? New Treatment Found
While fossil fuels — coal, oil, gas — still produce roughly 85 percent of the world’s energy supply, it’s clearer than ever that the future belongs to renewable sources such as wind and solar. The move to renewables is picking up the development around the world: They now account for more than half of new power sources going in operation.
Some growth stems from a commitment by governments and farsighted businesses to fund cleaner energy sources. But increasingly the story is about the falling prices of renewables, especially wind and solar. The cost of solar panels has dropped by 80 percent and the cost of wind turbines（涡轮机）by close to one-third in the past eight years.
In many parts of the world renewable energy is already an important energy source. In Scotland, for example, wind turbines provide enough electricity to power 95 percent of homes. While the rest of the world takes the lead, especially China and Europe, the United States is also seeing an amazing shift. In March, for the first time, wind and solar power accounted for more than 10 percent of the power generated in the US, reported the US Energy Information Administration.
President Trump has underlined fossil fuels — especially coal — as the path to economic growth. In a recent speech in Iowa, he dismissed wind power as an unreliable energy source. But that message did not play well with many in Iowa, where wind turbines dot the fields and provide 36 percent of the state’s electricity generation — and where tech enterprise like Microsoft are being attracted by the availability of clean energy to power their data centers.
The question “what happens when the wind doesn’t blow or the sun doesn’t shine?” has provided a quick remark for skeptics. But an increase in the storage capacity of batteries is making their ability to keep power flowing around the clock more likely.
The advance is driven in part by vehicle manufacturers, who are placing big bets on battery-powered electric vehicles. Although electric cars are still uncommon on roads now, this massive investment could change the picture rapidly in coming years.
While there’s a long way to go, the trend lines for renewables are zooming. The pace of change in energy sources appears to be speeding up — perhaps just in time to have a meaningful effect in slowing climate change. What Washington does — or doesn’t do — to promote alternative energy may mean less and less at a time of a global shift in thought.
1.According to Paragraph 3, the use of renewable energy in America ______.
A.has proved to be impractical B.is as common as in Europe
C.faces many challenges D.is progressing greatly
2.It can be learned that in Iowa ______.
A.wind is a widely used energy source
B.wind energy has replaced fossil fuels
C.there is a shortage of clean energy supply
D.tech enterprises are investing in clean energy
3.Which of the following is true about clean energy according to Paragraphs 5&6?
A.Its application has increased battery storage.
B.Its continuous supply is becoming a reality.
C.It is commonly used in car manufacturing.
D.Its sustainable exploitation will remain difficult.
4.It can be inferred from the last paragraph that renewable energy ______.
A.will bring the US closer to other countries
B.will accelerate global environmental change
C.is not really encouraged by the US government
D.is not competitive enough with regard to its cost
You know you have to read “between the lines” to get the most out of anything. I want to persuade you to do something equally important in the course of your reading. I want to persuade you to “write between the lines”. Unless you do, you are not likely to do the most efficient kind of reading.
I insist, quite bluntly, that marking up a book is not an act of damage but of love. There are two ways in which one can own a book. The first is the property right you establish by paying for it, just as you pay for clothes and furniture. But this act of buying is only the first step to possession. Full ownership comes only when you have made it a part of yourself, and the best way to make yourself a part of it is by writing in it. A comparison may make the point clear. You buy a piece of beef and transfer it from the butcher's icebox to your own. But you do not own the beef in the most important sense until you eat it and get it into your blood. I am arguing that books, too, must be absorbed in your blood to do you any good.
There are three kinds of book owners. The first has all the standard sets and bestsellers — unread, untouched. The second has a great many books — a few of them read through, most of them dipped into, but all of them as clean and shiny as the day they were bought. The third has a few books or many — every one of them worn, shaken and loosened by continual use, marked and scribbled (涂写) in from front to back.
Why is marking up a book necessary to reading it? First, it keeps you awake.(And I don’t mean only conscious; I mean wide awake. ) In the second place, reading, if it is active, is thinking, and thinking tends to express itself in words, spoken or written. The marked book is usually the thoughtthrough book. Finally, writing helps you remember the thoughts you had, or the thoughts the author expressed.
1.The third kind of owners of books must be ______.
A.experienced readers B.untidy readers
C.active readers D.careless readers
2.Marking up a book means ______.
A.writing down difficult sentences
B.finding the extra meanings of unknown words
C.writing in the space the ideas you get through careful reading
D.making notes to show you understand what you have read
3.What does the author persuade you to mark?
A.Whatever you have given deep thought to while reading.
B.Words and sentences that bring up rich ideas.
C.Primary questions that challenge you.
D.Whatever disagreements you may have with the book
4.A great advantage of marking up a book is ______.
A.to absorb all the brilliant ideas it contains
B.to make yourself a part of it
C.to make yourself conscious that you are reading actively
D.to enable yourself to pick up the book for continual reading
A family watching a dolphin from their boat were shocked when it dropped them off a cod (鳕鱼) supper for dinner.
The group were enjoying watching the mammal playing in the water when it suddenly dived down and caught the cod before placing it near to Lucy Watkins, 14.
The dolphin then appeared and began pulling the fish towards the stunned teenager. Lucy and her grandparents wondered whether they should pick up the fish in case the dolphin wanted it for tea.
But the dolphin then appeared seconds later with his own fish, this time a seabass (石斑鱼), and began eating. The family gratefully accepted the cod, which weighed about 10 pounds, before taking it home to cook for their dinner.
Lucy said, “He definitely wanted me to have his fish. He first dropped it 20 feet away but then pushed it to within 5 feet of my boat. Everyone was watching on the beach and we caused quite a stir (激动) when we came back with the cod.”
Grandmother Nina added, “It was as if he was saying to Lucy ‘Don’t worry, now I’ve got a fish to play with and so have you. This is mine for my tea; you have that one for yours.’ ”
“He was just so playful and content to be around us. Lucy was swinging her fingers in the water and he seemed to be attracted by that.”
“If I hadn’t seen it myself, I’d never have believed it. My theory is that he was lonely and wanted human company. He was with us for about two hours.”
“It seemed rude to refuse him so we took the fish and had cod and chips for supper. It was very large. I’ve still got half in the freezer.”
A spokesman from Whale and Dolphin Conservation said, “This is a very interesting account. There are many examples worldwide of dolphins interacting with humans. We would just make our usual appeal for people to generally keep their distance.”
1.What does the underlined word “stunned” probably mean?
A.Astonished. B.Upset.
C.Disappointed. D.Worried.
2.Why didn’t the family accept the cod at once?
A.Because Lucy’s grandparents didn’t like cods.
B.Because they were not sure whether it was a gift for them.
C.Because they didn’t know how clever the dolphin was.
D.Because they wanted to change for another one.
3.According to the text, we can infer that ________.
A.Lucy was afraid when she first saw the dolphin
B.Grandmother didn’t believe what the dolphin had done
C.the fish was delicious so they kept a half in the freezer
D.dolphins should be given their own living space
听下面一段独白，回答以下小题。
1.How long has the speaker lived in a big city?
A.One year. B.Ten years. C.Eighteen years.
2.What is the speaker’s opinion on public transport?
A.It’s comfortable. B.It’s time-saving. C.It’s cheap.
3.What is good about living in a small town?
A.It’s safer. B.It’s healthier. C.It’s more convenient.
4.What kind of life do the speakers seem to like most?
A.Busy. B.Colorful. C.Quiet.
听下面一段较长对话，回答以下小题。
1.How many Economics lectures will the man attend every week?
A.Five times, from Monday to Friday.
B.Two times, on Thursday and Friday.
C.Two times, on Tuesday and Thursday.
2.Why did the man miss the meeting for the new students yesterday?
A.He hadn’t received any notice about that meeting.
B.He had to attend the group discussion.
C.He had to do some part-time jobs yesterday.
3.If a student wants to earn the scholarship, what is the required attendance rate?
A.80% B.90% C.100%
4.Which of the following statements is NOT true according to the conversation?
A.The man is a grade one student in the university.
B.The man has to work after school.
C.The man thinks the time of the lecture is too early.
