Yesterday was written narration day in Preparing with my guy that is a great oral narrator but struggles with writing things down. It had already been a full day of writing and he was pretty exhausted from it. It was unit 4 where she begins having them write a sentence after just a couple of questions and really working them through it. I was writing down his sentences. Typically, I write them for him and then he copies them into his book. I had planned on not making him copy them into the book this time but I hadn't mentioned that to him. He was very halting in his answers, seemed like he wasn't really thinking and off in space. He was hesitant to say anything. Finally he said, "I could give a much narration if the sentences weren't going to be so long to have to write." I told him that he didn't have to copy them today and the final sentences were much better!
That is what happens in English and vocabulary when he has to make his own sentence. He thinks so hard to make one that is as short as possible when they could be much more creative.
So, my question is: what should I do about the written narrations. Is it better to have him write them and they be short choppy sentences without much detail? I know that what Carrie and Julie do in these cases is to see what the goal is for the particular activity. So, what would that be here?

Same with English and vocabulary, should I just let him make nothing sentences to have him actually writing it himself? That is what I have been doing, but when I ask him what his sentence would be if he didn't have to write it, it's always a very creative sentence.
Thanks!!