second nature

英文解釋：

名詞 second nature:

1. acquired behavior that is practiced so long it seems innate

例句：

1. After a while, driving becomes second nature to you.
   過不多久，開車的動作就像本能的反應一樣了。
2. Custom is a second nature.
   習慣是第二天性。
3. Habit is second nature.
   [諺]習慣是第二天性。