(Clearly, I got carried away with the Sorcerer's Stone quotes.)

• "'Yeh sure yeh're all righ'? Yeh look all hot an' bothered --'" (Hagrid)
• "'I must ask you not to scream,' said Lockhart in a low voice. 'It might provoke them.' As the whole class held its breath, Lockhart whipped off the cover. 'Yes,' he said dramatically. 'Freshly caught Cornish pixies.'"
• "'Never trust anything that can think for itself if you can't see where it keeps its brain.'" (Arthur Weasley)
• "'It is our choices, Harry, that show what we truly are, far more than our abilities.'" (Dumbledore)
• "'Because that's what Hermione does,' said Ron, shrugging. 'When in doubt, go to the library.'”