A citizen goes to buy a Trabant. The salesman tells him to come back to pick it up in nine (or ten) years.
The customer asks: “Shall I come back in the morning or in the evening then?”
The salesman asks: “You're joking, aren't you?”
The customer replies: “No, not at all. It's just that I need to know whether the plumber can come at 3:00 PM or not.