And the equation of state, pressure versus volume at constant temperature, is going to have some form, let's just draw it in there like that.

系统的态函数，恒温下压强比体积，变化曲线，就像这样。

麻省理工公开课 - 热力学与动力学课程节选

You know how pressure changes with temperature at constant volume if you know the equation of state.

如果你知道状态方程,知道在体积恒定的时压强如何随着温度变化。

麻省理工公开课 - 热力学与动力学课程节选

So now, this equation here relates three state functions together: the pressure the volume, and the temperature. Now, if you remember, we said that if you had a substance, if you knew the number of moles and two properties, you knew everything about the gas.

压强，体积和温度,大家应该还记得,我们提过，只要知道气体的摩尔数,和任意两个状态函数,就可以推导出其他的状态函数，这样，我们可以把它改写成。

麻省理工公开课 - 热力学与动力学课程节选