De Broglie has said electrons, under certain circumstances, can be modeled as behaving as though they are waves.

德·布罗意说过电子，在某种特殊的情况下，也可以运转，即使它们都只是波。

麻省理工公开课 - 固态化学导论课程节选

Suicide, under certain circumstances, might be rationally and morally justified.

自杀有时候，也有可能是合乎常理的。

耶鲁公开课 - 死亡课程节选