They smile and they kiss. In the English language, there are many expressions using the word mouth.

VOA: special.2010.06.20

The mouth moves up, particularly if somebody is attacking their record or ridiculing them, and they'll smile and--but it's not a sincere smile.

嘴唇移动，特别当有人攻击他们的记录,或嘲笑他们时，他们会微笑，但不是真诚的微笑。

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