Though the main direction does not change in a given period of time, within its ambit the secondary directions may shift at any moment; when we find ourselves checked in one direction, we must turn to another.

• 大方向虽在一个时期中是不变更的，然而大方向内的小方向则是随时变更的，一个方向受了限制，就得转到另一个方向去。