A collection is not just one basic idea. It comes from something that is in the air, something you suddenly like and put down on paper and then work out.
集合不仅仅是一个基本概念。它来自于空气中的某种东西，你突然喜欢上了它，然后把它写在纸上，然后再去做。
集合不仅仅是一个基本概念。它来自于空气中的某种东西，你突然喜欢上了它，然后把它写在纸上，然后再去做。