And they form little groups, all fighting with each other, and when I leave, two hours later, most of them are saying about 2 billion people, and they don't have any clue about how to get down to 2 billion, nor do I, but I think they're right and this is a serious problem.
他们分成小组，互相辩论， 我两小时后回来， 大多数人认为二十亿人口。 但是他们不知道怎么控制人口在二十亿。 我也不知道。但是他们是对的，这是个严重问题。