Why dein and not deine?
I believe this is because it's "der Mantel", a masculine noun. You use dein for masculine/neutral nouns and deine for feminine nouns.
Yes, see here: https://blogs.transparent.com/german/mein-dein-sein-ihr-etc-german-possessive-pronouns-in-the-nominative-case/
Thanks for sharing
Der - dein Die - deine Das - dein Die - deine
Mantel is masculin?!
Sounds really like older English. Thine mantel is long
I use jacket instead of coat and it was wrong but ive been using it on all the other statements and it has been correct. Also I said mucky instead of dirty and that was wrong
Can i use euer?
I think you could. As if the coat belongs to a group. But if you want to use formal you should use Ihr.
I am still learning; if i am wrong please correct me!
Couldn't this also be read as "my" coat is long? This form of Dein, how do you know its "your" vs "mine"