"Metgen: a girl?"
On the black-board:
"Why is it a girl?"
"Weil lang Hr hd: because she has long hair."
"And what has she not?"
"Moustache."
They next produced the likeness of man with no moustache.
"What's this?"
"Why is it a man?"
"Weil kurz Hr hd: because he has short hair."