But when that's not true, then there is a typical sort of modern frontier, a land bridge which there a line is-a theoretical line is drawn through it, and on one side is one city, and the other side is another city.

但还不止这些天然边界,另外还有种边界形式,和现代国境线很类似,是由一座陆桥,分割出一条界线…假象的界线,界线的一边是一个城邦,另一边是另一个城邦

耶鲁公开课 - 古希腊历史简介课程节选

So the line I've just drawn is the best response for Player I as it depends on Player II's choice.

我画的这条线表明参与人I的最佳对策,取决于参与人II的策略

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