It occurs as a result of something underlying which can be potentially serious."

VOA: special.2009.09.02

Every culture is going to have Pan Am smiles, happiness smiles, coy smiles, but the variation of that sort is something which will vary as a result of how you're raised and the people around you.

每一种文化都有问候式微笑，开心的微笑，腼腆的微笑，不同还在于,你是怎么被抚养大，你身边人如何。

耶鲁公开课 - 心理学导论课程节选