A reserved person is one who does not talk very much to strangers, does not show much emotion, and seldom gets excited.

一个谨慎的人不太会和陌生人聊天，不会流露出太多的情感，并且很少会兴奋。

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He is a very reserved person.

他是个很含蓄的人。

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Broadly speaking, the Englishman is a quiet, shy, reserved person who is fully relaxed only among people he knows well.

普遍看来，英国人是安静、羞涩和保守的，只有在自己熟知的朋友面前才会彻底地放松。

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Davis, pleasant and reserved in person, but intensely competitive in business, is the son of a middle-class lawyer.

FORBES: Double Dutch No Longer