【题目】Sleep is just as important as diet and exercise, and not getting enough sleep can lead to obesity, heart trouble and other health problems. Now scientists are adding more wake-up call to that list: lack of sleep damages the brain.

People who regularly have trouble falling asleep and staying asleep (one study drew the line at 6.8 hours ) show changes in brain-----actual shrinking(缩小),in some cases--- in area important for memory and problem solving.

Weve always believed that we can take the weekend to catch up and be fine, says Sigrid Veasey, a researcher in University of Pennsylvania, but that may not be the case. When she stopped mice from sleeping for 3 days, they lost 25% to 30% of the neurons (神经元) important for focused attention---- and these remaining were damaged. Whats more, these brain cells never grew again.

Clearly, something important is happening while we sleep, but exactly what sleep does for the brain has been a mystery. Thats why scientists got excited when researchers at the university of Rochester Medical Center recently offered a new theory. While observing the brains of sleeping mice, they discovered a kind of brain-cleaning system that clears away neural waste, the buildup of which is connected with Alzheimers.

In another study, young healthy people whose sleep was limited to 7 hours per night for one week showed damaged brain function. Scarier is that with long-lasting short sleep, you may feel fully rested. When study subjects were limited to 4 hours of sleep for 5 days, they reported feeling very tired following the first night but they didnt get any sleepier after that.

Whats more, a 15,000 person study found that getting an average of less than 5 hours of sleep per night for several years resulted in a decrease in memory performance equal to the brain aging 2 years.

Have we persuaded you to turn in early tonight ? Excellent.

【1】The text is mainly about _________.

A. how lack of sleep damages our brain.

B. why we feel rested without enough sleep.

C. how much sleep we should get every day.

D. Why we have trouble falling asleep sometimes.

2Sigrid Veaseys research shows that ________

A. lack of sleep doesnt affect our attention.

B. damaged brain cells can not recover.

C. sleeping on weekends can make up for lost sleep.

D. most neurons will die if we sleep poorly for 3 days.

3According to paragraph 5, after several days of short sleep people may feel _________.

A. tired B. sleepy

C. energetic D. angry

4According to the 15,000-person study, lack of sleep may cause ___________.

A. heart trouble B. obesity

C. death D. memory loss

【题目】根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Cycling

Both children and adults ride bicycles for fun and for exercise. Some people use bicycles for transportation because it is less expensive than traveling by car. 【1】__.

The sport of cycling consists of races that are held mostly on roads or tracks. 2 .The first recorded race in the United States was held in 1878 in Boston, Massachusetts. The most famous bicycle race, the Tour de France, began in 1903. Cycling is also a part of the Summer Olympic Games.

Sport cycling includes road races for men, women and children. Some races cover short distances of 2.5 to 3 miles.__3 .A stage race consists of a series of races held over several days or even weeks.

Time trials (计时赛) are a type of competition in which cyclists do not race directly against each other. Instead, individual cyclists or teams are timed as they ride separately over a certain distance._4_ .Most stage races include time trials.

Several types of bicycle races are held on an oval (椭圆形的) track. The track may be either indoors or outdoors. In the high-speed races, cyclists compete against each other over a short distance. The pursuit (追逐赛) is an event in which cyclists start on opposite sides of the track and try to catch each other. 5 .The motorcycle cuts through the wind, which normally slows a bicycle down. As a result, cyclists can go much faster than they can in other races.

A. It takes three weeks to complete.

B. Others cover hundreds of miles.

C. The cyclist or team with the faster time wins.

D. The world’s best riders compete in it.

E. In a motor-paced race, each cyclist rides behind a motorcycle or motorbike.

F. Others use bicycles for transportation because bicycles do not pollute the air.

G. Sport cycling began in 1868 with a race near Paris, France.

【题目】Driving to a friend’s house on a recent evening, I was attracted by the sight of the full moon rising just above my friend’s rooftop. I stopped to watch it for a few moments, thinking about what a pity it is that most city people --- myself included --- usually miss sights like this because we spend most of our lives indoors.

My friend had also seen it. He grew up living in a forest in Europe, and the moon meant a lot to him then. It had touched much of his life.

I know the feeling. Last December I took my seven-year-old daughter to the mountainous jungle of northern India with some friends. We stayed in a forest rest house with no electricity or running hot water. Our group had campfires outside every night, and indoors when it was too cold outside. The moon grew to its fullest during our trip. Between me and the high mountains lay three or four valleys. Not a light shone in them and not a sound could be heard. It was one of the quietest places I have ever known, a bottomless well of silence. And above me was the full moon, which struck me deeply.

Today our lives are filled with glass, metal, plastic and fiber-glass. We have television, cell phones, electricity, heaters and ovens and air-conditioners, cars, computers.

Struggling through traffic that evening at the end of a tiring day, most of it spent indoors, I thought, “Before long, I would like to live in a small cottage. There I will grow vegetables and read books and walk in the mountains. And perhaps write, but not in anger. I may become an old man there, and wear the bottoms of my trousers rolled and measure out my life in coffee spoons. But I will be able to walk outside on a cold silent night and touched the moon.”

【1】 The best title for the passage would be _________.

A. Touched by the Moon

B. Break away from Modern life

C. A Bottomless well of Silence

D. The Pleasures of Modern Life

2The writer felt sorry for himself because __________.

A. there was too much pollution.

B. he failed to see the fullest moon.

C. he didn’t adapt to modern inventions

D. there were too many accidents on the road.

3Modern things are mentioned mainly to ___________.

A. show that the writer likes city life very much.

B. tell us that people greatly benefit from modern life.

C. explain that people have less chances to enjoy nature.

D. show that we can also enjoy nature at home through them.

4The author wrote the passage to __________.

A. show the love for the moonlight.

B. want to communicate longing for modern life.

C. advise modern people to learn to live.

D. express the feeling of returning to nature.

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