You’re JOKING!” said Fred Weasley loudly.
The tension that had filled the Hall ever since Moody’s arrival suddenly broke. Nearly everyone laughed, and Dumbledore chuckled appreciatively.
“I am not joking, Mr. Weasley,” he said, “though now that you mention it, I did hear an excellent one over the summer about a troll, a hag, and a leprechaun who all go into a bar...”
Professor McGonagall cleared her throat loudly.
“Er — but maybe this is not the time... no...” said Dumbledore.

Auteur: J.K. Rowling