题目内容

we may spend an all night studying before an important exam.We'll most probably rush to rescue a broken down friend in the middle of the nigh, 1. All that can leave you feeling unsure of how you're going to survive the day ahead.If you would like some helpful tips on how to stay alert,read on to find out more:

.Nap

This may seem obvious but it goes without saying that the antidote(解药)to tiredness is sleep. 2.

According to Dr David Dinges,editor of the journal SLEEP,a nap as short as 10minutes can be of benefit to you by moving the brain into slow-wave‘sleep.According to ranges,sleeping for longer than 40 minutes could leave you feeling slightly groggy(昏沉) upon waking,but this will soon wear off. 3.

. 4.

Though this is not a long term solution it does do the trick temporarily.The average person needs around 100-200 milligrams of caffeine.5. The benefits will last for around three to four hours.

A.Caffeine doesn't work.

B.Drink caffeinated drinks.

C.Lack of sleep is becoming more and more common in our society.

D.If you haven't got time for 8 hours then try taking a short nap instead.

E.It will take around 15 to 30 minutes for it to come into effect.

F.Occasionally we are just unable to sleep because of anxiety.

G.You will feel sharper after that.

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At thirteen, I was diagnosed(诊所) with kind of attention disorder. It made school difficult for me. When everyone else in the class was focusing on tasks, I could not.

In my first literature class, Mrs.Smith asked us to read a story and then write on it, all within 45 minutes. I raised my hand right away and said,”Mrs.Smith, you see, the doctor said I have attention problems. I might not be able to do it.”

She glanced down at me through her glasses, “you are no different from your classmates, young man.”

I tried, but I didn’t finish the reading when the bell rang. I had to take it home.

In the quietness of my bedroom, the story suddenly all became clear to me. It was about a blind person, Louis Braille. He lived in a time when the blind couldn’t get much education. But Louis didn’t give up. Instead, he invented a reading system of raised dots(点), which opened up a whole new world of knowledge to the blind.

Wasn’t I the “blind” in my class, being made to learn like the “sighted” students? My thoughts spilled out and my pen started to dance. I completed the task within 40 minutes. Indeed, I was no different from others; I just needed a quieter place. If Louis could find his way out of his problems, why should I ever give up?

I didn’t expect anything when I handled in my paper to Mrs.Smith, so it was quite a surprise when it came back to me the next day- with an ”A” on it. At the bottom of the paper were these words:”See what you can do when you keep trying?”

1.The author didn’t finish the reading in class because.

A. He was new to the class

B. He was tried of literature

C. He had an attention disorder

D. He wanted to take the task home

2.What do we know about Louis Braille from the passage?

A. He had good sight

B. He made a great invention.

C. He gave up reading

D. He learned a lot from school

3.What was Mrs.Smith’s attitude to the author at the end of the story?

A. Angry B. Impatient

C. Sympathetic D. Encouraging

4.What is the main idea of the passage?

A. The disabled should be treated with respect.

B.A teacher can open up a new world to students.

C. One can find his way out of difficulties with efforts.

D. Everyone needs a hand when faced with challenges.

Scientists at Harvard University have recycled a kidney(‘肾)-in a rat. The researchers removed a kidney from a dead rat. Later, the renewed kidney was put into a living rat. It wasn't perfect. It did, however, show signs of working like a kidney should.

"It's really beautiful work," Edward Ross, a kidney researcher at the University of Florida in Gainesville, told Science News. He didn't work on the new study.

Kidneys are bean-shaped and act like guards in the body. They clean the blood by removing waste and extra water. Every day, an adult's kidneys filter(过滤) enough blood to fill a bathtub half full. Along the way, they produce eight cups of urine(尿) from that waste and water. When a person's kidneys fail, all of that waste stays in the body. Such patients can quickly become very sick and die, unless they are regularly connected to a machine that filters their blood.

At any given time, about 100,000 people in the United States are waiting for a replacement kidney. But healthy donated kidneys are difficult to get. Either a living person must donate one, or a kidney must be removed from someone who just died and earlier had agreed to the donation. In either case, people receiving new kidneys face the risk that their bodies will reject the donated ones.

But there may be another option. Researchers use knowledge of living things to grow or improve tissue that can aid human health. Harald Ott's team at Harvard started with a "used" kidney.

Scientists added kidney cells from rats and blood vessel cells from people to the matrix(母体). These cells attached themselves and began to multiply. Before long, they formed new kidney tissue.

The scientists placed this renewed kidney into another rat. There it produced a small amount of urine. This experiment shows that the lab-grown kidney can do at least some of the work performed by a healthy kidney.

The results are a promising first step toward helping people with serious kidney problems. "This is still very early, but they've come a long way," Ross said.

1.What can we infer from Paragraph l?

A. Biology is a new and helpful science.

B. It's hard to put the rebuilt kidney into the rat.

C. Kidneys are very important to our life.

D. A used kidney may be recycled for new life.

2.What does Paragraph 3 mainly talk about?

A. The relationship between kidneys and health.

B. The difficulty of curing serious kidney diseases.

C. The function and importance of kidneys.

D. The methods of curing kidneys diseases.

3.For what purpose does the author use the figure 100,000 in Paragraph 4?

A. To stress used kidneys are hard to get.

B. To show the great need for healthy kidneys.

C. To explain many American people get kidney diseases.

D. To call on people to donate kidneys.

4.Which of the following is true according to the text?

A. The scientists are satisfied with the result of the experiment.

B. Ross is a kidney expert who is involved in the experiment.

C. The function of the renewed kidney is the same as a healthy kidney.

D. The renewed kidney produced a great deal of urine.

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