On my birthday, I got a gift certificate from my wife. The certificate paid for a visit to a shaman or medicine man living on a nearby Indian reservation who was rumored to have a wonderful cure for erectile dysfunction. After being persuaded, I drove to the reservation, handed my certificate to the shaman, and wondered as to the future.
The old man slowly and methodically produced a potion. He handed it to me, and with a grip on my shoulder, warned, 'This is powerful medicine and it must be respected. It works only when the moon is full. You take only a teaspoonful and then say, '1-2-3.' When you do that, you will be longer and harder than you have ever been in your life and you can perform as long as you want.'
I was encouraged. As he walked away, I turned and asked, 'How do I stop the medicine from working?'
'Your partner must say '1-2-3-4' when she's had enough,' the shaman replied. 'But when she does, the medicine will not work again until the next full moon.'
I was eager to see if it worked. I went home, showered, shaved, took a spoonful of the medicine, and then invited my wife to join me in the bedroom. When she came in, I took off my clothes and said, '1-2-3!' Immediately, I was the manliest of men.
My wife took one look at me. She was so excited she began throwing off her clothes.
She jumped onto the bed and excitedly asked, 'What was the '1-2-3' for?'
And that, boys and girls, is why we should never end our sentences with a preposition.