Energy can flow across the glass but I put a lid on top, and so the water can't get out.

能量可以穿过杯壁流动,但是我在顶上加了盖子，所以水不能跑出来。

麻省理工公开课 - 热力学与动力学课程节选

A state where it's closed, so imagine a channel with a lid on top of it; when it's closed nothing can go through the channel, when it's open then things can go through.

一种是闭合状态,想想一个有盖子的通道吧,当盖子合上的时候任何东西都不能通过,而打开时就畅通无阻

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