Always try to give people the benefit of the doubt. Not for their sake, but for yours. Maybe they don't have any experience with a pws. They don't understand the impact of their actions. Simply looking somebody in the eye and telling them that you have a speech impediment will usually set them on their heels. You don't have to ask him not to mock you. Nor ask them to apologize. Just looked them in the eye and tell them that you've had a stutter all of your life.