We're also going to recognize, however, that insurance got a slow start because-- I believe it is because-- people could not understand the concept of probability.

不管怎么说,我们得承认,保险起步缓慢,因为...,我相信是因为...,人们无法理解概率的概念

耶鲁公开课 - 金融市场课程节选

Then you get successively deeper, II through IV, slow, irregular, high amplitude delta waves, and then once you reach stage IV you start going up again, up through stage III and II.

然后睡得越来越深，从第二到第四阶段，慢，不规则，高振幅的δ波，等你到达第四阶段，你又开始返回，第三阶段和第二阶段。

耶鲁公开课 - 心理学导论课程节选