—Do you know how old the old man is?

—Maybe he is 70 years old, but I can't say it __________.

A.exactly B.quickly C.easily D.luckily

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(E)

The World Wide Web（www.萬維網(wǎng)）turned 25 years old on March 12th. It has become a very important part in our daily lives. We can’t imagine living without the web, the short form of the World Wide Web.

In 1989, a British engineer named Tim Berners-Lee came up with the idea of the Web. It is a group of “pages” of information that are connected to each other around the world. That is the very beginning of the Web. Since then, the Web has greatly changed the way people live. With a click(點(diǎn)擊)of a mouse we can read news, buy things, make friends and learn anything we’re interested in.

Now, 25 years after its birth, how will the Web influence life in the future? Scientists believe there are both advantages and disadvantages. w W w .x K b 1.c o M

A growing Web will help build “better relationships” between different cultures. Also in the future, everyday items could be connected to the Web. We could share plenty of information to make our daily lives more convenient(方便的). So one day in the future, your front door could send you a message. “Dear sir, everyone has left the house, but I’ m still open!”

But scientists warn（警告）us that if we share personal information on the Internet it could get into the wrong hands.

“It’s not wise to spend a whole day in front of the screen. People need to get close to nature and enjoy the sun. Never be controlled by the Internet.” said Berners-Lee.

1.How old is the World Wide Web?

2.Who came up with the idea of the Web?

3.What can we do by clicking a mouse according to the passage?

4.Will the Web influence life in the future?

5.What could happen if we share personal information on the Internet?

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As a matter of fact, Lucy is good at dancing.

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You might have learned in your science classes that the sun is quite large and heavy. What if you heard that we’ve found a black hole that contains the mass (質(zhì)量) of nearly 70 suns?

Chinese scientists used LAMOST, a powerful Chinese telescope (望遠(yuǎn)鏡), as well as telescopes in Hawaii and the Canary Islands, to make this discovery.

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D.By looking at the speed of a star that orbits it.

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