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

But they spent a lot of time, energy, and money on being sure that they would have a supply of water to hold them for a long siege.

他们花费了大量的时间,精力,和金钱来确保,在长期的围城中他们可以获得足够的水源

耶鲁公开课 - 古希腊历史简介课程节选