"I do think you might be underestimating precisely what magic can do," Hermione says, sounding worried. "Some of it I can't even give you examples of, I'm afraid, just descriptions, but there are three curses in particular from my world, that you ought to- you know what, I'll keep quiet until we've actually got a place to practice, shall I?"

She looks brisk and businesslike, and continues; "I had thought of a place- an old playing field, it's out of the way and not used anymore- where were you thinking of?"