1. Both. When it is a letter, it's usually the first one in the word, but those are not that bad, at least compared to when I can't say one whole word - that's much worse. 2. Yes. I would like to give you examples, but I'm not a native speaker, so it's a bit different in my language. Maybe one of them could be A, because my name starts with it and I have troubles with saying it sometimes. Also, the word Google can be difficult to say... 3. I actually never paid attention to that one, but I'll try in the future. 4. Every time. 5. Reading yes, singing no, but I can't rap. 6. Exchanging words, definitely. Avoiding direct eye contact and maybe even speaking less loud. Lately, I try to concentrate on my breathing and talking more slowly. 7. As I said in 6, definitely. I do that more often than I like to admit. ​ P.S. Out of curiosity, are you doing this research for yourself, like for fun, or something else?