We have 266, as some of you might know who saw me counting ping-pong balls the other day in office hours.

看到了这些发泡胶球事实上,可以当作单层金原子核,我们有266个乒乓球。

麻省理工公开课 - 化学原理课程节选

Well, we're talking about a pretty high number here, so to make counting easier, we'll just say 10 lone pairs, because 20 lone pair electrons is the same thing as 10 lone pairs.

好吧，我们这里讨论的是一个挺大的数，为了数起来更容易，我们就说有十对孤对电子，因为二十个跟十对是一个意思。

麻省理工公开课 - 化学原理课程节选

Most censuses were taken, by the way, as a way of counting heads, the number of people who had to be fed at the time of a siege.

顺便提一下,大多数人口普查,都采用数人头的方法,即在围城期间统计需要给养多少人口

耶鲁公开课 - 欧洲文明课程节选