Do you mean ter tell me," he growled at the Dursleys, "that this boyโthis boy!โknows nothin' abou'โabout ANYTHING?" Harry thought this was going a bit far. He had been to school, after all, and his marks weren't bad. I know some things," he said. "I can, you know, do math and stuff.
J. K. RowlingOh, I'm so glad we know what it's called, that's a great help," snarled Ron, leaning back, trying to stop the plant from curling around his neck.
J. K. RowlingHow do you remember everything from different books when you are still writing the HP series? As obsessive fans will tell you, I do slip up! Several classrooms move floors mysteriously between books and these are the least serious continuity errors! Most of the fansites will point you in the direction of my mistakes. But the essentials remain consistent from book to book because the story has been plotted for a long time and it is clear in my mind.
J. K. RowlingWhat are you doing with all those books anyway?" Ron asked. Just trying to decide which ones to take with us," said Hermione. When we're looking for the Horcruxes." Oh, of course," said Ron, clapping a hand to his forehead. "I forgot we'll be hunting down Voldemort in a mobile library.
J. K. Rowling