But just as biologists can fairly claim to know all the major types of, say, land mammals, astronomers are on the verge of identifying all the major classes of light-emitting objects.
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- 但就像生物学家所宣称,他们能够认识陆生哺乳动物所有的主要类别,天文学家也几乎可以辨识发光天体的所有主要类型。