There's infinite number of them, but they're all moving relative to each other at constant velocity.

有无数个惯性观察者,但是他们都在相对于彼此,做匀速运动

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That's a very large number, it's all relative, so you don't necessarily know it's large without me telling you or giving you other ions to compare to, but chlorine does have a very large affinity, meaning it's really likes getting an electron and becoming a chlorine ion.

这是个非常大的数值，这种数值都是相对的，因此你不一定能知道这是非常大的,除非我告诉你或给你另外离子数值作为参考，但是氯确实有很高的电子亲和能，这意味着它非常乐意得到一个电子,而变成一个氯离子。

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