Now those oligarchies were based on different things, and that's where the rub came.

但这些寡头是建立在不同基础之上的,正是这一点导致了双方的摩擦

耶鲁公开课 - 美国内战与重建课程节选

Every time I drive the steering wheel of my car, I rub off some items. But that's OK, it's still the very same physical object.

每次我使用方向盘时，都会摩擦掉一些微粒，但没关系，它还是原来那个物体。

耶鲁公开课 - 死亡课程节选