A new mother,for example, quickly learns to try to sleep when her baby is quiet, even in the middle of the day.

VOA: special.2010.01.31

Having said all that, let me just--oops, try to turn this baby on.

讲完这点以后,我们来看几张幻灯片

耶鲁公开课 - 欧洲文明课程节选