You have a vocal handicap that is severe enough to affect your day to day life and your ability to communicate with others.
-1: Something akin to a broad dialect that makes your speech at least partially unintelligible with the local language.
-2: A speech impediment such as a strong lisp or inability to pronounce certain sounds.
-3: A speech impediment so severe that it can sometimes completely stop you from getting across what you want to say. A strong stammer is an example.
-4: You are vocally mute and must communicate through other means, such as gestures or writing.