It was a short way of writing a different spelling of the words all correct. Some foreign-born people wrote all correct as o-l-l k-o-r-r-e-c-t, and used the letters O.K.

VOA: special.2010.02.28

So, we can put our sulfur in the middle, and then it doesn't really matter how we draw the rest of it, where we put our c l's versus where we put our oxygen.

那么，我们可以把硫放在中间，然后把其它的原子画在哪里就不重要了，把两个氯原子与一个氧原子放在哪里都行。

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