I have all three. The blocks are more common for me than repetitions or prolongations, which is unfortunate because the people around me in real life do not understand the concept of a block that well. My blocks are so bad that I just stay quiet sometimes because I can't get the words out. I'm not a very talkative person as it is, so I look extra quiet and serious when I don't mean to be. Repetitions and prolongations do happen but I don't hate them as much.