The boring answer is... it depends and often varies from person to person, but here's mine 1. Oh yes. Very much so. We're fully aware. Many (if not all) already know when we start a sentence which word we're gonna block at. We spend the time reaching that part of the sentence trying to find a word to replace it with, or re-structure the sentence entirely. Sometimes, both fails and we end up hopelessly stuck anyway. 2. Depends. Normally, I hate it with a burning passion when people do that. I realize it is coming from a good place and the person finishing for me is only trying to help, but please; wait instead. Exceptions are when the person is OK with it of course. For me, sometimes when I get hopelessly stuck, I just give my girlfriend "the look" and she takes over. But that's my way of asking for it, so of course in that sitiuation that's not something I consider rude. 3. Very individual. Some try to hide it as much as possible, some (like me) often mention it as soon as possible to sort of let the cat out of the bag so to speak. Personally, I do that because it lessens the tension a bit for myself, which makes me stutter less. If you ask, in a respectful way, she will probably tell you. One thing that many have in common though, is that for reasons unknown, we like to talk about the condition. If you genuinely ask, chances are she will tell you what you want to know. But again, this also depends. Some absolutely hate that part of themselves and wants to bury it as deep as possible. In mu opinion, the best you can do is listen patiently. Let her finish. She will notice and she will undoubtedly appreciate it and chances are that over time she will stutter less and less in front of you. I didn't find your topic rude. I found it more like a person who was genuinely interested in a topic, and asked in a respectful manner. Show your stuttering friend the same amount respect, and you