Many people become bitter, rather than better, and never grow up.

很多人不但没有因苦难而成长，反而变得苦毒。

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Some people never grow up but get stuck in one phase or another of human development.

有些人永远不会长大，而是卡在了常人成长的某个阶段。

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Unless you try to do something beyond what you have already mastered, you will never grow up.

你不尝试着做些能力之外的事情，就永远无法成长。

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They can never grow up with the sweet naivety that makes childhood carefree.

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Some people, it seems, never grow up.

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