Thus just as earlier theories have explained the mobility of the continents, so hot spots may explain their mutability (inconstancy).

因此，正如早期的理论解释了大陆的流动性，热也可以解释它们的易变性（不稳定性）。

This outward mutability indicated, and did not more than fairly express, the various properties of her inner life.

这种外在的易变性表，是公平地表达了她内心生活的各种特性。