I love the scene where the spiders want Ron to tap-dance
One of my favorites, that I also use a lot is
"Don't let the Muggles get you down" - Ron
(used a lot in conversation also, "no post on sundays" and "I shouldn't have said that, I should not have said that" and "I WAS DISTRAUGHT!" and "why couldn't it be follow the butterflies" and "I'd like a nice cup of tea, or a large brandy" .......we have also have "always" engraved in our wedding bands)
other favorites are:
"Actually, I'm highly logical, which allows me to look past extraneous detail and perceive clearly that which others overlook." - Hermione
"You foul, loathsome, evil little cockroach" -Hermione (that whole scene is brilliant)
"You may not like him Minister....but you can't deny...Dumbledore's got style" -Kingsley (movie) Phineas (book)
Harry: "Hagrid warned me about the dragons."
Ron: "No, I did! Don't you remember? I told Hermione to tell you that Seamus told me that Parvati told Dean that Hagrid was looking for you! Seamus never actually told me anything, so it was really me all along. I thought we'd be alright, you know, after you figured that out."
Harry: "Who... who could possibly figure that out? It's completely mental. "
"I suspect the Nargles are behind it" - Luna
"Anyway, my mum always said things we lose have a way of coming back to us in the end." - Luna
"I don't think you're a waste of space" - Dudley
"She needs to sort out her priorities" - Ron
"Working hard is important. But there is something that matters even more, believing in yourself. Think of it this way; every great wizard in history has started out as nothing more than what we are now, students. If they can do it, why not us?" - Harry
"Percy wouldn't recognize a joke if it danced naked in front of him wearing Dobby's tea cozy." - Ron
"It does not do to dwell on dreams and forget to live" - Dumbledore
'Happiness can be found, even in the darkest of times, if one only remembers to turn on the light.' - Dumbledore
"Of course it is happening inside your head, Harry, but why on earth should that mean that it is not real?" ' Dumbledore (he has sooooo many good quotes)
"The ones that love us never really leave us." - Sirius (we used this one on the memorial at the wedding)
"The house of Godric Gryffindor has commanded the respect of the wizarding world for nearly ten centuries. I will not have you, in one night, besmirching that name by behaving like a babbling, bumbling band of baboons! " - McGonagall
Mad-Eye Moody: "For those of you who haven't taken Polyjuice Potion before, fair warning. It tastes like goblin piss."
Fred: "Have a lot of experience with that, do you, Mad-Eye? ...Just trying to defuse the tension."
I could probably go on all night
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