A duck walks into a pub and heads straight for the bar. He asks the barman, "Have you got any bread?"

"No sorry, we don't sell bread."

"Have you got any bread?"

"No, I just told you, we don't have any bread."

"Aw right then. What about bread? Do you have any bread?"

"Look you stupid little duck, I don't have any bread! And if you ask me for it one more time, I'm going to nail your beak to this bar!"

The duck pauses to think. "Have you got any nails?"

"No."

"Have you got any bread?"