The cost of a thing is the amount of what I will call life which is required to be exchanged for it, immediately or in the long run.
一件东西的代价，就是你必须当下或日后拿来交换它的那一部分生命。
— Henry David Thoreau · Walden (1854) —
键盘照着敲一遍，更容易记住。
不用找输入框，直接敲键盘。