Mine is mostly repetition but I do get the odd block too. There are different types of repetition and I forget which one my old speech therapist said it is. I don't stutter on every word or every other word like I've heard some others do. In saying that, I do prolong some words to try and avoid the stutter and there are some words that are very hard to not stutter on. I usually struggle with stutter, Saturday, limited and monitoring. It also depends on the phrase and the way the sentence is structured too, which I find odd tbh