I just showed you that you can have a single wave, a double, a triple and so on.

我想说的是你能得到单个波，双波，三条波等等。

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So, if something cycles through five wavelengths in a single second, we would just say that the frequency of that wave is five per second.

如果一个东西在一秒,内经历了五个波长，我们就说这个波的,频率是每秒5次。

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