Chapters 2 and 4 are really reviews of things that you probably already know something about, so they're reviews of basic chemistry.

第二章和第四章是对,一些你可能已经知道的,基础化学,蛋白质及生物化学知识的复习

耶鲁公开课 - 生物医学工程探索课程节选

Let's review another point and I'll get to a second question that was asked.

现在让我们复习另一个知识点，我将给出第二个问题。

耶鲁公开课 - 聆听音乐课程节选