Professor Snape walks angrily around the classroom. He stalks around the classroom like a lion with the students being his prey. “There will be no foolish wand-waving or silly incantations in this class. As such, I don't expect many of you to appreciate the subtle science and exact art that is potion-making.” He looks at you with his piercing black eyes. “Do I make myself clear?” He seems to be waiting for your response.