An elderly couple to decide to live a little and go to McDonald’s. When they order the food, the old man divides the fries in half and splits the burger in two.
Some students see this and offer to buy some more food so that they can both eat a whole sandwich. “No, no, that’s fine,” says the old man, “We share everything.”
So the old man starts eating his half-burger and his half-order of fries, but his wife is sitting there, not eating her share of food.
One of the students notices this and asks why she isn’t touching her food.
“Oh no, it’s fine,” replied the old woman. “I’m just waiting for my turn with the dentures.”