The following is a Liste of some of their greatest moments. Most of these are from the books. However, these first two are from the DH1movie. Enjoy!
Moody: Fair warning: it tastes like goblin piss.
One twin: How do Du know what that tastes like? *sees Moody's glare* Just trying to ease the tension.
Both: *after transformation* Wow. We're identical.
Ok. Here we go with Zitate from the books. Don't forget to comment. Also, add any I may have missed.
"Fred, Du next," the plump woman said.
"I'm not Fred, I'm George," sagte the boy. "Honestly woman, Du call yourself our mother? Can't Du tell I'm George?"
"Sorry, George, dear."
"Only joking, I am Fred," sagte the boy, and off he went.
"Blimey," sagte the other twin. "Are you--?"
"He is," sagte the first twin. "Aren't you?" he added to Harry.
"What?" sagte Harry.
"Harry Potter," chorused the twins.
"Aaah, has ickle Ronnie got somefink on his nosie?" sagte one of the twins.
"Hang on, I think I remember him saying something about it," sagte the other twin. "Once--"
"Blown up a toilet? We've never blown up a toilet."
"Great idea, though, thanks, Mom."
"Never mind that, do Du think he remembers what You-Know-Who looks like?"
"We'll send Du a Hogwarts toilet seat."
"We got Potter! We got Potter!"
"You must be good, Harry, Wood was almost skipping when he told us."