题目内容
According to the passage, which of the following is NOT true of elliptical galaxies？
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There are three main types of galaxy: spiral, elliptical, and irregular. The Milky Way is a spiral galaxy, a flattish disc of stars with two spiral arms emerging from its central nucleus. About one-quarter of all galaxies have this shape. Spiral galaxies are well supplied with the interstellar gas in which new stars form. as the rotating spiral pattern sweeps around the galaxy it compresses gas and dust, triggering the formation of bright young stars. The elliptical galaxies have a symmetrical elliptical or spheroidal shape with no obvious structure. Most of their member stars are very old and since ellipticals are devoid of interstellar gas, no new stars are forming in them. The biggest and brightest galaxies in the universe are ellipticals with masses of about 1013 times that of the sun, these giants may frequently be sources of strong radio emission, in which case they are called radio galaxies. About two-thirds of all galaxies are elliptical. Irregular galaxies comprise about one-tenth of all galaxies and they come in many subclasses.
Measurement in space is quite different from measurement on Earth. Some terrestrial distances can be expressed as intervals of time, the time to fly from one continent to another or the time it takes to drive to work, for example. By comparison with these familiar yardsticks, the distances to the galaxies are incomprehensibly large, but they too are made more manageable by using a time calibration, in this case the distance that light travels in one year. On such a scale the nearest giant spiral galaxy, the Andromeda galaxy, is two million light years away. The most distant luminous objects seen by telescopes are probably ten thousand million light years away. Their light was already halfway here before the Earth even formed. The light from the nearby Virgo galaxy set out when reptiles still dominated the animal world.
What does the second paragraph mainly discuss？
【28】
【39】
I am very interested in people, in meeting them and 【28】______ about them. Some of the most 【29】______ people I've met existed only in a Writer's imagination, then 【30】______ the pages of his book, and then, again, in my imagination. I've found in books new friends, new societies, new words.
If I am interested in people, others are interested not so much in who 【31】______ in how. Who in the books includes everybody from science-fiction superman two hundred centuries in the future all the way back to the first 【32】______ in history; how 【33】______ everything from the ingenious explanations of Sherlock Holmes 【34】______ the discoveries of science and ways of teaching manners to children.
Reading can make our minds feel pleased, 【35】______ means that it is a little like a sport: your eagerness and knowledge and quickness 【36】______ you a good reader. Reading is 【37】______ , not because the writer is telling you something, 【38】______ because it makes your mind work. Your own imagination works together with the 【39】______ or even goes beyond his. Your experience, 【40】______ his, brings you to the same or different conclusions, and your ideas develop as you understand his.
【21】
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