The structure of a star can often be thought of as a series of thin nested shells, somewhat like an onion.

恒星的结构经常被想象成一系列套在一起的薄层，就像洋葱一样。

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The structure of an onion allows us to perform the skin-peeling exercise several times, progressing ever deeper into the onion’s inner secrets with every skin peeled off.

我们能够对一个洋葱图结构进行多次脱皮，不断将每层皮剥落，直到进入到洋葱的内心。

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In structure it is somewhat like a transparent onion, formed of roughly 22,000 very fine layers.

在结构上，它有点像一个透明的洋葱头，约由22,000片很薄的层组成。

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