Not being to able to speak your mind. When experiencing a block, it's a feeling that I personally can't describe because I physically cannot say the word. It's like something is stopping my lips from moving the way I want them to and I have no control of it whatsoever. There's a lot of mental blocks at times that also stop me from talking that is impossible for me to overcome. Honestly for non stutterers, stuttering is difficult to grasp unless you stutter yourself.