Kurumi's hand shot up in the air. She had been doing lots of research recently on house elves, trying to figure out what was wrong with them and what would cause them to not meet their own standards. After all, house elves were immensely loyal creatures, so it was odd that they would be behaving in such a fashion. "Excuse me, professor," Kurumi said, knowing that she would be backing up the discussion just a bit. "House elves were first brought to Hogwarts by Helga Hufflepuff. She did so due to the horrible abuse they were receiving from witches and wizards. In bringing them to Hogwarts, Helga Hufflepuff ensured that at least a small number of the house elves would not be living and working in abusive conditions." She paused for a few moments to collect her thoughts. "You could say that this gesture contributed to the house elves fighting back during the Battle of Hogwarts centuries later. Granted, this was probably also connected to them being loyal by nature." And now her hand was going down.
She thought for a moment about how best to answer this one. Defining expression by using express seemed to be a little...redundant? Such airy and complex words were often hard to describe anyway. "I have always thought of an expression or saying as a set phrase that communicates an idea. Sometimes this idea has moral standards and sometimes it is a set of rules that should be followed. Or...sometimes it is just silly." Which she sometimes thought about the Hogwarts' motto.