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There was an older married couple sitting on their porch swing.

They continued to swing for awhile, then suddenly the old woman
punched her husband as hard as she could. He fell from the swing
and went flying down the porch steps.

He got up, dusted himself off and said,” What the hell was that for?"

"That was for 50 years of bad sex!" was her reply.

He sat down and they swung a little bit more. Then suddenly the old
man slapped his wife across the face as hard as he could, knocking
her to the floor.

She got up, dusted herself off, and asked, "What the hell was that for?!"

Came the reply: "That's for knowing the difference!"
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