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课时规范训练(单独成册) 训练(二十二) Ⅰ.阅读理解 阅读下列短文，从每题所给的四个选项(A、B、C、D)中，选出最佳选项。 A Not too big，not too small.Not too hot，not too cold.A newly discovered planet looks just right for life as we know it，according to an international group of astronomers. Orbiting a star about 500 lightyears away，the planet called Kepler186f is about the same size as the Earth.It orbits its star at the right distance for liquid water on the surface.That is an essential condition for life.But it is not exactly like the Earth.It’s more of an Earth’s cousin.It’s not an Earth’s twin.It shares the same characteristics as the Earth，but their parent stars are very different. Kepler186f orbits a star that is smaller and cooler than our sun.But the planet appears to be a closer relative than most of the hundreds of others discovered so far.Some are massive gascovered giants with thick atmospheres.Others orbit too closely to their stars and are too hot for life.For the first time，we can actually say we now have a planet that is both Earthsized and orbits in its star’s habitable zone. The next step would be to look for signs of life in the atmospheres of these distant worlds.That would take a more complicated space telescope.“But budget cuts threaten that mission，” says University of California at Los Angeles astrophysicist Ben. | 
