You could take a continuous path, where you have an infinite equilibrium points in between the two, a smooth path, whereyoudrop pressureand temperature simultaneosly in little increments.

你可以选择光滑的连续路径，在初末态间有,无数个平衡态的点，压强和温度同时一点,一点地下降。

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Then you put something else that you know in your mind, which is that the highest point is the point when it's neither going up nor coming down.

然后你就想到了些东西,也就是说,最高点,就是那个既不上升也不下降的点

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