So most of you know, hopefully, that a mule is a combination of a donkey and a horse.

希望大部分同学都知道，骡子是驴和马的一种组合。

麻省理工公开课 - 化学原理课程节选

A mule is not spending 1/2 of its time as a donkey, and 1/2 of its time as a horse, we don't see it flickering back and forth between the two, that's not what we see.

骡子并不是一半的时间是驴，另一半的时间是马，我们不会看到它在两者之间来回变化，这不是我们所看到的情况。

麻省理工公开课 - 化学原理课程节选

A good example to keep in mind is the idea of a mule.

大家可以记住一个很好的例子，那就是骡子。

麻省理工公开课 - 化学原理课程节选