•Harry Potter and the Philosopher's Stone
Dudley: They stuff people's heads down the toilet the first day at Stonewall. Want to come upstairs and practice?
Harry: No, thanks. The poor toilet's never had anything as horrible as your head down it -- it might be sick.
•Harry Potter and the Philosopher's Stone
1st Weasley Twin: Oh, are you a prefect, Percy? You should have said something, we had no idea.
2nd Weasley Twin: Hang on, I think I remember him saying something about it. Once --
1st Weasley Twin: Or twice --
2nd Weasley Twin: A minute --
1st Weasley Twin: All summer --
Percy: Oh, shut up!
•Harry Potter and the Philosopher's Stone
Professor McGonagall: Well, thank you for that assessment, Mr Weasley. Perhaps it would be more useful if I were to transfigure Mr Potter and yourself into a pocket watch. That way, one of you might be on time.
•Harry Potter and the Philosopher's Stone
Dumbledore: I was unfortunate enough in my youth to come across a vomit-flavored one, and since then I have rather lost my liking for them. But, I think I could be safe with a nice toffee. (eats it)
Dumbledore: ...Hmm, alas, earwax.
•Harry Potter and the Philosopher's Stone
(in the Devil's Snare)
Hermione: Stop moving, both of you. This is devil's snare! You have to relax. If you don't, it'll only kill you faster!
Ron: Kill us faster? Oh, now I can relax!
•Harry Potter and the Philosopher's Stone
Harry: So light a fire!
Hermione: Yes... of course... but there's no wood!
Ron: HAVE YOU GONE MAD! ARE YOU A WITCH OR NOT!
•Harry Potter and the Chamber of Secrets
Ron: "A Study of Hogwarts' Prefects and Their Later Careers." That sounds fascinating.
•Harry Potter and the Chamber of Secrets
Fred: Oh get out of the way, Percy. Harry's in a hurry.
George: Yeah, he's off to the Chamber of Secrets for a cup of tea with his fanged servant.
•Harry Potter and the Chamber of Secrets
Ron: Why spiders? Why couldn't it be "follow the butterflies"?
•Harry Potter and the Chamber of Secrets
Ron: Can you believe our luck? Of all the trees we could've hit, he had to get one that hits back.
•Harry Potter and the Chamber of Secrets
Draco: Sure you can manage that broom, Potter?
Harry: Yeah, reckon so
Draco: Got plenty of special features, hasn't it? Shame it doesn't come with a parachute-in case you get too near a Dementor. (Crabbe and Goyle sniggered)
Harry: Pity you can't attach an extra arm to yours, Malfoy. Then it could catch the Snitch for you.
•Harry Potter and the Prisoner of Azkaban
Ron: Right, you've got a crooked sort of cross… (consulting "Unfogging the Future") That means you're going to have 'trials and suffering' -- sorry about that -- but there's a thing that could be a sun… hang on… that means 'great happiness'… so you're going to suffer but be very happy…
Harry: You need your Inner Eye tested, if you ask me…
•Harry Potter and the Prisoner of Azkaban
Professor Lupin: Now repeat after me -- without wands please -- repeat after me, Riddikulus.
Class: Riddikulus!
Professor Lupin: And again!
Class: Riddikulus!
Malfoy: This class is ridiculous.
•Harry Potter and the Prisoner of Azkaban
Hermione: Ancient Egyptians used to worship cats, you know.
Ron: Yeah, along with the dungbeetle.
•Harry Potter and the Prisoner of Azkaban
Professor Trelawney: The study of Divination will give you the rare gift of SIGHT! (stands up, and promptly bumps into her table)
•Harry Potter and the Prisoner of Azkaban
Professor Trelawney: Would anyone like me to help interpret the shadowy realms within their orb?
Ron (whispering to Harry): I don't need help. It's obvious what this means. There's going to be loads of fog tonight.
•Harry Potter and the Prisoner of Azkaban
Ron to Pettigrew (with revulsion): I let you sleep in my bed!
•Harry Potter and the Goblet of Fire
Fred Weasley: Anyone can speak Troll, All you have to do is point and grunt.
•Harry Potter and the Goblet of Fire
Ron: Don't talk to me.
Hermione: Why not?
Ron: Because I want to fix that in my memory forever…
Ron (his eyes closed): Draco Malfoy, the amazing bouncing ferret...
•Harry Potter and the Goblet of Fire
Percy: I shudder to think what the state of my in-tray would be if I was away from work for five days.
Fred: Yeah, someone might slip dragon dung in it again, eh, Perce?
Percy: That was a sample of fertilizer from Norway! It was nothing personal!
Fred (whispering to Harry): It was. We sent it.
•Harry Potter and the Goblet of Fire
Hermione: You seem to be drowning twice.
Ron: Oh, am I? I'd better change one of them to getting trampled by a rampaging Hippogriff.
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I hope these are helpful.