A young man had been walking through the streets all day and was very thirsty（t a）。 Finally he went into a shop and asked the shop keeper, How much are these cakes you have here？
Five cents each, " was the answer I'll give you ten cents for three of them.
All right，"said the shopkeeper.
So the young man took three cakes and then began looking at some of the other things in the shop.“ How much is this wine（酒）？”he asked Ten cents a glass Well, I'm more thirsty than hungry. Here, take back the cakes and give me a glass of wine.
So the shopkeeper gave him a glass of wine. The young man drank the wine and began to walk out of the shop Just a minute, young man, said the shopkeeper. "You havent paid for the wine.”
Of course not. I gave you the cakes for it.
But you didn't pay for the cakes.
I didn't eat them. I gave them back to you. I certainly don' t have to pay for something I didnt eat, do I？ And before the shopkeeper could think of an answer to that the young man was out of the shop.