...like, useful ones, or, like, "capybara".

Useful ones! Prepositions, conjunctions, common nouns like person, cave, danger, food, dom, sub, etc.

Huh. She will try to indicate with her slate and chalk that he should write small but otherwise she'll let him get on with it.

He can do so, organizing words as he goes, to make it easy to sort through. He's sort of deciding this system on the fly and probably he can do a much better job if he'd planned ahead of time how to sort words, oh well.

She puts her coins away and pulls out her folding chair and desk that are made of bones and unfolds them while he's at it. He is welcome to sit in the chair at the desk if he would like, it'd make writing easier.

If she gestures for him to use the chair he'll do it, otherwise he's fine where he is and will let her have the desk.

She goes back to sitting in her hammock with a notebook of her own.

So long as she's not using it he'll sit at the desk, figure out a better organizational system, and write. 

When he's slowing down she will cast again and look over his shoulder.

His list of words is now color coded, and neatly laid out on multiple pages.

She skims through it. Can she compose "stay here while I am gone for several hours"?

Yep! She doesn't even need to leave the first page for that.

"Is there food here that is safe for me to eat while you are gone?"

Can she do "yes, a small person will bring you food"?

Yep, "bring" is on the second page.

"Okay, um. Thank you for being so helpful."

"You're welcome," she taps. Off she goes.

It isn't long before a small person brings him a bowl of mushroom stew.

Oh good Lucien was an unwise amount of famished.

The small person comes back for his bowl a few minutes later.

Lucien can clean his own bowl...but not in this circumstance so sure, the small person can have the bowl.

The purple woman is back after about six hours.

There are now five more pages of densely packed words, a pronunciation guide, a table of contents, and - mostly but not entirely redundant with the table of contents - an instructional flow chart to tell you what page and section various things are in.

...sigh.

She ushers him out of the desk chair; she has stuff to do with this scroll and this book.

-oh no what did he do.

She is not going to tell him right now! Instead she is going to do her inscrutable book thing.

He will sit on the floor patiently and wait.