题目内容

In today’s world, sleep experts often say that for a better night’s rest, Americans should turn o1. their smart phones or iPads before sleeping. Such electronic products make the brain more 2.(act), and then influence their sleep. But according to a latest survey, more than 90% of Americans often use a computer or some other 3.(kind) of electronic products in the hour before bed.

Researchers find that man-made light from some electronic products at night may reduce the brain chemicals that help to s4.. In the study, the researchers let volunteers read, play games and watch movies on a screen for different time while measuring(测量) 5. much light their eyes received. They found that two hours of 6.(sit) before a bright screen at night reduced the sleep chemical levels by about 22%.

Then the researchers studied the college students who often 7.(use) computers at night. They got the s8. results. And researchers say that may not only cause sleeplessness, but 9. raise the risk of obesity(肥胖症), diabetes(糖尿病)and other diseases.

To be on the safe side, the researchers suggest that we should use computer 10.(little) than before, or turn down our screens as much as possible before sleeping.

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Every day there is less and less space on Earth for rubbish. Yet every day we make more and more rubbish. What can we do? We can recycle some of our rubbish. Recycling means that the rubbish will be made into something that can be used again.

Recycling helps Earth. And it saves space in rubbish dumps. Half of everything that we put into landfills could be recycled instead. In fact, most things made of paper, metal, glass and plastic can be recycled.

Paper can be broken into small pieces and made into new paper. Steel and aluminum cans(金属雄)can be melted down(熔化)and made into new cans. The same is true of glass bottles. This can be done aver and over again. Recycling doesn't take as much energy as making these things the first time. So we can use less of Earth's fuel resources.

Plastic can be melted down, too. Then it can be formed into park benches, playgrounds and so on. Some people call plastic the "wood" of the future. Things made of plastic will last about 400 years-even if they stay outside in the weather. No wood can do that!

1.The underlined word "landfills" in Paragraph 2 probably means _____________.

A.bench factories B.places for rubbish

C.green mountains D.recycling centres

2.According to the passage, what happens last to the can?

A.The can is put into a recycling bin. B.The can is melted down and reused.

C.A steel can gets filled with corn. D.A person uses the corn in the can.

3.What is the main idea of the passage?

A.Cans should be melted down.

B.Old newspapers can be reused.

C.We can build benches that last 400 years.

D.We should recycle everything that we can.

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