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Air is a colorless, tasteless and invisible（看不見的）gas that is around us. An “empty” drinking glass and an “empty” room, in fact, are not really empty. Each is filled with air. When the glass is filled with water, the water pushes the air out of the glass.
Air, as a gas, has no definite shape, but because it is matter, it takes up space and it has weight. It is easy to prove that air is something that takes up space. Stuff a piece of dry cloth（布）into the bottom of a glass so that it will not fall out when the glass is turned upside down. Push the upside down glass, holding straight up and down, into a jar of water till the glass is completely covered. When the glass is taken out of the water, the cloth is still dry. The air inside the glass shows that it takes up space and keeps the water from coming in.
【小題1】Since air is matter, it has ________.

Air is a colorless, tasteless and invisible（看不見的）gas that is around us. An “empty” drinking glass and an “empty” room, in fact, are not really empty. Each is filled with air. When the glass is filled with water, the water pushes the air out of the glass.

Air, as a gas, has no definite shape, but because it is matter, it takes up space and it has weight. It is easy to prove that air is something that takes up space. Stuff a piece of dry cloth（布）into the bottom of a glass so that it will not fall out when the glass is turned upside down. Push the upside down glass, holding straight up and down, into a jar of water till the glass is completely covered. When the glass is taken out of the water, the cloth is still dry. The air inside the glass shows that it takes up space and keeps the water from coming in.

1.Since air is matter, it has ________.

A．room , and weight as well                 B．both room and shape

C．either room or weight                    D．neither shape nor weight

2.The word “Stuff” means ______ in Chinese.

A．撕               B．蓋               C．取掉             D．塞

3.The writer tells that the experiment（實(shí)驗(yàn)）___________.

A．is carried out in the space                 B．must be done in the lab

C．is made in the room                     D．can only be done in the open air

One day when Isaac Newton was reading a book under an apple tree on the farm，an apple fell down and hit him on the head．For most people that would be the end of the story，but not for Newton．Why did the apple fall out of the tree? Does everything fall? What makes things fall? Can anything stop things from falling? Are the sun，moon，and stars falling? Why don't they ever hit the ground?

Newton spent many years answering these questions by thinking and doing experiments．He made up the law of gravity（引力定律）．According to this law everything pulls everything else to itself by a force（力）called gravity．How strong that force is depends on how heavy the things are and how close together．

Newton's law of gravity not only explained how things fall on earth，but how planets move around the sun and how moons move around planets．A friend of his，Edmund Halley，decided to try Newton's theory（理論）on comets（彗星）．People had been studying comets for hundreds of years but failed to understand them，so he decided to study their reports and compare them to Newton's theory．

Up till then people had thought that comets just came and went，and that nobody could know when or why．But Newton's law of gravity gave rules that Halley could use to study the records of comets．He found some reports of a big bright comet that he was sure was the same one，coming back every 75 years．He predicted（預(yù)測）when it would come back next．

Halley's prediction came true．Tile comet appeared at the right time as he predicted using Newton's ideas．This was enough to convince anybody who still didn't believe Newton．Halley's Comet has come a few times since then，always right on time．You'll be able to see it on its next trip near the sun and earth when you're old enough to be a grandparent．

1．The passage starts with a story to show _______．

A．it was such a funny one

B．Newton liked to eat apples

C．how much Newton liked reading

D．what led to Newton's discovery of gravity

2．How strong gravity is depends on _______ of the things according the Newton’s theory．

A．color and distance（距離）                      B．weight and distance

C．size and weight                                          D．size and color

3．According to the writer，Newton was especially different from others in that _______．

A．he liked reading under apple trees              B．he liked to find out how things worked

C．he was very quiet and patient                             D．he was so much interested in science

4．The underlined word convince in the last paragraph probably means “make people _______”．

A．believe                 B．doubt                   C．understand             D．relax

5．Which of the following is true about Edmund Halley?

A．He discovered a big bright comet

B．He helped Newton to create his theory．

C．He predicted when the same comet would come back．

D．He studied the comet for 75 years

Very few people enjoy exams. I don’t, either. And although I tell myself not to worry about them, I always do! So I’m not surprised that my students worry about them, too, even though they usually don’t need to. Because they are afraid of failing. However, since it is hard not to worry at all, we all must try not to worry too much. Why? Because worrying makes exams worse! How to do this?
Ask the teacher about how to revise and about exam skills—how to work when you are in the exam. Good students don’t wait until the week before an exam. They study all through the year. It is not possible to learn everything at the last minute. So don’t leave it till then.
If you start planning and working for each exam early and you make sure that you understand what you’re studying, then, when it is over, you’ll be able to say, “What a good exam that was!”
Take a short rest during your time of work and revision. If your mind is tired, it won’t remember well. Work at the time when you know you’ll work at your best.
If you’re studying in the evening, don’t go straight to bed afterwards. Your mind will still be “going round and round”—thinking too much. Do something else, maybe walk or get exercise. Choose something that will relax you, and make you think of other things.
If you feel bad, talk to someone about your worries. But don’t be too relaxed! Some stress over exams makes you work hard for them.
【小題1】How does the writer feel about exams?