Now, so there's probably a number of people in this room, so when I first started teaching this class 20 years ago, everybody in the room had had chickenpox.

现在,这间教室中的很多人也许,在二十年前,我第一次教这门课的时候,当时教室里的每个人都得过水痘

耶鲁公开课 - 生物医学工程探索课程节选