Some people like to use an arrow, and the arrow points in the direction of the more electronegative end.

也可以用箭头，箭头指向,带负电的一极。

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That's what this arrow at the right shows, the direction of the flow of information.

这就是右边这个箭头的含义,即信息流动的方向

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p2 p1 is greater than p2. Then I want to reverse direction of time. I want the arrow of time to go so that the gas goes from p2 to p1.

一直推，一直推，p1大于,接下来我想让时间倒流,让气体从p2到p1。p2比p1小。

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