I’m not sure of the original source of this. As you can see it’s from a tweet, but I’d love to know where it originally came from …
“Adjectives in English absolutely have to be in this order: opinion-size-age-shape-colour-origin-material-purpose Noun. So you can have a lovely little old rectangular green French silver whittling knife. But if you mess with that word order in the slightest you’ll sound like a maniac. It’s an odd thing that every English speaker uses that list. but almost none of us could write it out. And as size comes before colour, green great dragons can’t exist.”