What we came up with was an idea to exploit an old fact, or a known fact, about social networks, which goes like this: Do you know that your friends have more friends than you do?
我们想出来的方法 是采用了一个古老的事实， 或者说关于社交网络的已知事实， 这个事实是这样的： 你知道你的朋友 有比你更多的朋友吗？