I've heard that people finish a tree while they're at level 13 or so. What happens after that? When a tree's finished, what makes the level go up til 25?! Just curious!
It depends on what strategy or what is your scope. Some people here repeat. the tree many times. Some others do the strengthening exercises. The first one gives you more XPs, depending on your mistakes, in mobile version max. 5 per each lesson. Some others prefer to change the language or even try the opposite tree.Or even wait till the tree becomes fainted again
No, you don't :-)
I am at 37% with my Portuguese course.
If you are learning the language from scratch, review is the key (fighting against the forgetting curve).
Do you use Memrise in parallel?
I do, and the SR algorithm has additional short-term goals on newly learned words (3-8/12/24h++ review intervals), even for 25-50% finished Memrise course levels (not so for DuoLingo).
This will let you practice more the learned words, where you can find out your weak / difficult vocabulary.