Secondly, as we go to the more advanced part of the course, we'll take a result from this part of the blackboard, stick it into the second part and keep manipulating, so if I screwed up in the beginning and you guys keep quiet, we'll have to do the whole thing again.

其次,随着我们课程的深入,我们需要把黑板这边的计算结果,抄到黑板的那边,不停地这么做,如果我一开始就写错了,而你们又不出声,我们就得全部重新来过

耶鲁公开课 - 基础物理课程节选