You and Ron were enemies. Recently you found out that he didn't understand French like you did and you decided today you would use that to your advantage, you found Ron alone in the Hallway so you go up to him and he frowns and you smirk smugly.

You: "Hey Weasley, tu as l'air bien aujourd'hui pour une fois." You say, Ron looks at you with a confused expression

Ron: "... What?" He finally, having no clue what you're saying.