You need a substance and then that substance has to have a property that changes depending on the heat flow, i.e., depending on whether it's sensing that it's the same temperature or different temperature than something else.

你需要某种物质,它的某种性质,随着热量的流动而改变，也就是说,依赖于它是否感觉到它,与其他的物体处于相同的温度。

麻省理工公开课 - 热力学与动力学课程节选

And there's a certain property associated with heat flow with b and it didn't change.

具有某种与热量流动有关,的特定的性质,它是不变的。

麻省理工公开课 - 热力学与动力学课程节选

You've got a property that changes, depending on the heat flow.

它的某种性质，随热量的流动变化。

麻省理工公开课 - 热力学与动力学课程节选