Related, I sometimes carry a piece of paper that says "I am in the middle of a sentence. Let me finish." My blocks are so long that I show that paper sometimes. If someone responds to a half of my sentence, usually I can say "that's not the end of a sentence!" in a singing way and do not need that piece of paper. But it is when someone responds too soon in an impatient tone, that is when I freeze and just show the paper.