City Girl Goes Farming

Nancy, a city girl, married a farmer.  One morning, before the farmer went out to the field, he said, "Honey, today the artificial insemination man is coming over to impregnate one of the cows.  I put a nail in a two-by-four over the cow's stall.  Please show him which one it is."

When the guy arrived, Nancy led him down the row of stalls until she saw the nail.  She pointed to the stall, and he asked her, "Are you sure this is the one?"

"Yes, I'm sure.  It's the one with the nail," said Nancy.

"What's the nail for?" asked the man.

"I guess it's to hang your pants on," replied Nancy.