如果说一个人在假装地高兴或故作镇定，好像什么事情都没有，就可以说 put on a brave face 即装作若无其事的样子。

例句

Mary didn't get the promotion she was expecting. But she put on a brave face and went to the office party.

The athletes put on a brave face when they left the stadium, where the team had suffered its worst defeat in ten years.

请注意

另一个短语 two-faced 的意思是两面派，人前人后言辞不一。

Frederick is two-faced. He keeps telling me he loves my work, while he says to my colleagues that he thinks I should be sacked.