孩子拿书的方式会告诉你他们对这本书的全部感受。
Topology is the study of the properties of a figure that are unchanged by any deformation.
"I hope that in this year to come, you make mistakes. Because if you are making mistakes, then you are making new things, trying new things, learning, living, pushing yourself, changing yourself, changing your world. You're doing things you've never done before, and more importantly, you're doing something."