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Air is a colourless, tasteless, invisible gas that surrounds the planet Earth. It is everywhere on the planet. An 'empty' drinking glass and an 'empty' room, to give two examples, 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 (一定的) shape, hut, because it is matter, it takes up spacE.It is easy to prove that air is something that takes up spacE.Stuff a dry handkerchief 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, hold 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 handkerchief will be dry. The air inside the glass took up space and kept the water from coming in.
What's the article mainly about?
A.Air is a kind of gas.
B.Air is invisiblE.
C.Air is everywherE.
D.Air takes up spacE.

A.B.
What's
C.Air
D.
B.Air
E.
C.Air
F.
D.Air

【参考答案】

D
解析：整篇文章都在讲空气虽然无色无味，但它确实存在，而且占据着一定的空间。
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Bees and ColorOn our table in the garden we put a blue card, and all around this blue card we put a number of different gray cards. These gray cards are of all possible shades of gray land include white and black. on each card a watch-glass is placed .The watch-glass on the blue card has some syrup (果汁) in it; all the others are empty. After a short time bees find the syrup, and they come for it again and again. Then, after some hours, we take away the watch-glass of syrup which was on the bluecard and put an empty one in its placE.Now what do the bees do? They still go straight to the blue card, although there is no syrup therE.They do not go to any of the gray cards, in spite of the fact that one of the gray cards is of exactly the same brightness as the blue carD.Thus the bees do not mistake any shade of gray. for bluE.In his way we have proved that they do really see blue as a color.We can find out in just the same way what other colors bees can seE.It turns out that bees can see various colors, but these insects differ from us as regards their color-sense in two very interesting ways. Suppose we train bees to come to a red card, and, having done so, we put the red card on the table in the garden among the set of different gray cards. This time we find that the bees mistake red for dark gray or black. They cannot distinguish between them. This means that red is not a color at all for bees; for them it is just dark gray or black.That is one strange fact; here is another. A rainbow is red on one edge, violet on the other. Outside the violet of the rainbow there is another color which we cannot see at all. This color beyond the violet, invisible to us, is called the ultra-violet. Although it is invisible, we know that the ultra -violet is there because it affects a photographic platE.Now, although we are unable to see ultra -violet light, bees can do so; for them ultra -violet is a colon Thus bees see a color which we cannot even imaginE.This has been found out by training bees to come for syrup to various parts of a spectrum, or artificial rainbow, thrown by a prism on a table in a dark room. In such an experiment the insects can be taught to fly to the ultra-violet, which for us is just darkness.Experiment with bees described in the first and second paragraphs tell us that bees regard blue as a colonA.TrueB.FalseC.Not mentioned
A.The
B.
Now
C.
We
D.
That
E.
Experiment
F.True
B.False
C.Not
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Jeans were invented a little over a century ago and are currently the world's most popular, versatile garment, crossing boundaries of class, age and nationality. From their origins as pure workwear, they have spread through every level of the fashion spectrum, and are embraced internationally for their unmatched comfort and appeal.In the mid 1940s, the Second World War came to an end, and denim blue jeans, previously worn almost exclusively as workwear, gained a new status in the U. S. and EuropE.Rugged but relaxed, they stood for freedom and a bright futurE.Sported by both men and women, by returning GI's and sharp teenagers, they seemed as clean and strong as the people who chose to wear them. In Europe, surplus Levi's were left behind by American armed forces and were available in limited supplies. It was the European population's first introduction to the denim apparel. Workwear manufacturers tried to copy the U. S. originals, but those in the know insisted on the real thing.In the 1950s, Europe was exposed to a daring new stylE.in music and movies and consequently jeans took on an aura of sex and rebellion. Rock'n'roll coming from America blazed a trail of defiance, and jeans became a symbol of the break with convention and rigid social morals. When Elvis Presley sang in 'Jailhouse Rock', his denim prison uniform. carried a potent, virile imagE.Girls swooned and guys were quick to copy the King. In movies like 'The Wild One' and 'Rebel Without a Cause' cult figures Marion Brando and James Dean portrayed tough anti-heroes in jeans and T-shirts. Adults spurned the look; teenagers, even those who only wanted to look like rebels, embraced it.By the beginning of the 1960s, slim jeans had become a leisure wear staple, as teens began to have real fun, forgetting the almost desperate energy of the previous decade, while cocooned (包围在) in wealth and security. But the seeds of change had been sown, and by the mid 1960s jeans had acquired yet another social connotation—as the uniform. of the budding social and sexual revolution. Jeans were the great equalizer, the perfect all-purpose garment for the classless society sought by the Hippy generation. In the fight for civil rights, at anti-war demonstrations off the streets of Paris, at sit-ins and love-ins everywhere, the battle cry was heard above a sea of bluE.Jeans were first designed for ______.A.soldiersB.workmenC.teenagersD.cowboys
A.B.
C.
D.
Jeans
E.
A.soldiers
B.workmen
C.teenagers
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