[EWillers]

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DAMNIT ITS TWO PAIR

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Damnit it's "it's" when used as a contraction and "its" when used as a possessive. I only bring it up due to the irony of poor grammar in a post relating to grammar/diction.

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"Two pairs" is grammatically correct. If you have one pair (that's singular because there is only one).

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I think the thinking behind the poker usage of "two pair" lay in the idea that at a showdown every player has exatctly one "category" of hand. "Two pair" is a category just like "straight" or "one pair".

Personally I use "two pairs", but can definitely see either as being acceptable.