You just need to express in ASCII character, one at a time, and these brave souls are simply going to spell something out for us to hammer home this point of binary.

你们只需要每人代表一个ASCII码，这些勇敢的小伙子们就是想,清楚的让大家理解二进制原理。

哈佛公开课 - 计算机科学课程节选

whenever you want to express what you are doing at a particular moment in time.

当你想表达在某一时刻你在做的事情时，你都可以用这个句型。

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