A man buys several sheep, hoping to breed them for wool. After
several weeks, he notices that none of the sheep are getting
pregnant, and calls a  vet for help. The vet tells him that he shouldtry artificial insemination.
The farmer doesn't have the slightest idea what this means but, not wanting to display his ignorance, only asks the vet how he will know when the sheep are pregnant. The vet tells him that they will stop standing around and instead will lie down and wallow in grass when they are pregnant.
The man hangs up and gives it some thought. He comes to the conclusion that artificial insemination means he has to impregnate the sheep.
So, he loads the sheep into his Landrover, drives them out into
the woods, has sex with them all, brings them back and goes to bed.
Next morning he wakes and looks out at the sheep. Seeing that they are all still standing around, he deduces that the first try didn't take, and loads them in  the  Landrover again.
He drives them out to the woods, bangs each sheep twice for good measure brings them back and goes to bed. Next morning, he wakes to find the sheep still just standing round. One more try, he tells himself, and proceeds to load them up and drive them out to the woods.
He spends all day shagging the sheep and, upon returning home, falls  listlessly into bed. The next morning, he cannot even raise himself from the  bed to look at the sheep. He asks his wife to look out and tell him if the sheep are lying in the grass. "No," she says, "they're all in the Landrover and one of them is beeping the horn."