题目内容

In the days before electricity, people don’t worry much about sleep. They usually went to bed a couple of hours after sunset (日落) and woke at sunrise. After all, there wasn’t much to do in those days after the sun went down. But then came the electric light bulb (电灯泡). And now we have satellite television, the Internet,24-hour convenience stores, and longer hours at work. How much can we sleep? How much should we sleep?

Like it or not, many of us are sleeping less on average (平均). In 1910, most Americans slept 9 hours a night. That dropped to 7.5 hours by 1975. In 2002, a study by the National Sleep Foundation found that the average American got only 6.9 hours. The news is even worse for people who work the night shift. They sleep an average of just 5 hours.

Are we sleeping enough? Not if you believe in the old rule of eight hours of rest, eight hours of work, and eight hours of play. On the other hand, Norman Stanley, a British scientist who studies sleep, believes people’s sleep needs are different. Some people need as many as 11 hours, but others need as few as three. How much do you really need? “To find out,” he says, “simply sleep until you wake naturally, without the help of an alarm clock. That’s your sleep need.”

Meanwhile, other scientists and researchers are searching for new ways to keep us awake longer. Some are developing chemicals (化学药品) that are safer and more powerful than caffeine, the chemical found in coffee and tea. One experimental drug, CX717, kept laboratory monkeys working happily for 36 hours. Further developments may allow people to safely stay awake for several days straight. One group of researchers is studying a gene (基因) found in some fruit flies that lets them get by on one-third the usual amount of sleep. Another group is even working on an electric switch that immediately wakes up a sleeping brain.

The meanings of this research are huge. On the one hand, this could lead to a world where we work longer and longer hours with less and less sleep. On the other hand, if we needed less sleep, we would have more free time to travel, read, volunteer, and spend time with family.

1.How many hours did most Americans sleep a night in 1975?

A. 5. B. 6.9. C. 7.5. D. 9.

2.What can we learn from the passage?

A. People have got enough sleep. B. People will work longer hours.

C. Sleep time will be a big problem. D. Staying awake for long is possible.

3.What is probably the best title of the passage?

A. To sleep or Not to sleep? B. How can We Sleep Longer?

C. To Work or Not to Work? D. How Much We can Sleep?

1.C 2.D 3.A 【解析】我们到底每晚需要多少睡眠呢?过去我们总是认为至少要八个小时的睡眠,但文章中作者告诉我们,不同的人需要的睡眠时间也是不一样的。而且现在科学家们和研究人员还在寻找一些新的方法可以让人们清醒的时间更长。 1.细节理解题。根据短文第二段中Like it or not, many of us are sleeping less on average (...
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Kaitlin Riffel’s dream to end poverty(贫困) started when she was visiting her father, who worked for the homeless.

"I never realized there were people in the world who didn’t have a home or food before," said Kaitlin, who is now sixteen. "I knew there was something I had to do about that."

At age eight, she started raising money to build a playground. "It took me two years," Kaitlin said. "We started small. We wanted to do something to make a difference."

In 2014, When Kaitlin was thirteen, she visited Central America, and saw people going hungry and families living in houses made of cardboard. That year, we set Kids on a Mission, which has helped hundreds of people there.

"The rooms were smaller than my bedroom, but there would be eight people living in each one," Kaitlin said. "We also got to see the dirty rivers that those people were drinking out of."

Providing clean drinking water, food and clothes for people living in poverty is now an important task for Kids on a Mission. "This young lady is changing the hearts of people, and also changing the world," said the headmaster of Kaitlin’s school.

1.The job of Kaitlin’s father was to__________.

A. sell foods B. build playgrounds

C. visit schools D. help homeless people

2.When did Kaitlin set Kids on a Mission?

A. In 2009. B. In 2011. C. In 2014. D. In 2017.

3.What was people’s life like in Central America according to Kaitlin?

A. They lived in strong houses.

B. Their drinking water was dirty.

C. Their bedrooms were very big.

D. They had enough food and clothes.

4.What can we infer from the headmaster’s words?

A. Kaitlin is always ready to give and help.

B. Kaitlin has many chances to travel around.

C. Kaitlin often changes schools for her study.

D. Kaitlin has a serious problem with her heart.

5.What might be the best title for the text?

A. School life in America B. Gift from a headmaster

C. Father’s duty in the family D. Girl’s dream to end poverty

1.D 2.C 3.B 4.A 5.D 【解析】试题分析:这篇短文主要介绍了Kaitlin从很小的年龄就开始为改变世界帮助别人而努力,结束贫穷是她的梦想。 1. 2. 3. 4. 5.

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