1. Raise an eyebrow, as if questioning what the fuck they're doing, works pretty well. Can also add this to question with your hands, usually works. ​ 1. Depending on the type of confrontation, raising the middle finger is always a clear sign of being disagreeable. ​ 1. If it's with friends that you've stuttered around before, it's fun to add salt saying "Oh thanks" // "oh jeez thanks", or faking a prolonged stuttering. I wouldn't stay quiet, respond in some way whether it's talk or a sign of you hearing it, doesn't really matter. But you don't wanna seem like you didn't understand you were being provoked.