An old couple enters a restaurant.
W: Are you ready to order?
M: Yes, a steak for me, and a cup of vegetable soup for my wife.
W: Certainly.
The couple finishes their meals and leaves.
Five minutes later, they come into the restaurant again.
W: Oh, hello again, can I take your order?
M: Oh yes, a cup of vegetable soup for me, and a steak for my wife.
W: Oh I see, but why didn't you order them last time?
M: Because we have only one set of false teeth.
