Hearing voices no one else can hear isn't a good sign, even in the wizarding world.

You know, I don’t get why Fred and George only got three O.W.L.s each,” said Harry, watching as Fred, George, and Lee collected gold from the eager crowd. “They really know their stuff. . . .” “Oh, they only know flashy stuff that’s no real use to anyone,” said Hermione disparagingly. “No real use?” said Ron in a strained voice. “Hermione, they’ve got about twenty-six Galleons already. . . .

Don't count your owls before they are delivered.

A lemon drop. They're a kind of Muggle sweet I'm rather fond of.

Like the fact that the person Sirius cared for the most about in the world was you," said Dumbledore quietly.

He's a werewolf! That's why he's been missing classes!

Why are you worrying about YOU-KNOW-WHO, when you should be worrying about YOU-NO-POO? The constipation sensation that's gripping the nation!