Smiles are social signals.

微笑是社交信号。

耶鲁公开课 - 心理学导论课程节选

So if the landscape invites him to grow as an imaginative person, the social world he lives in, this episode signals to us immediately, will never live up to that imagination.

假如生活氛围使他,成为一个充满想像力的人，那么他所处的社会就是这一时期，这会让我们马上感到，那种想象永不可能成真。

耶鲁公开课 - 1945年后的美国小说课程节选