And, we enter into a contract. You walk in here, you have certain expectations of me.

我们就定下了契约，我走进来，你对我会有所期待。

麻省理工公开课 - 固态化学导论课程节选

And, believe it or not, I have students walk in and first thing a hand goes up and says do you have a pen? I cannot believe it.

不管信不信，我有些学生走进来，第一件事就举起手问,你有没有笔，难以置信。

麻省理工公开课 - 固态化学导论课程节选