Which CEFR level will a beginner reach after completing the Turkish course??
Is it B1 or A2??
I've completed the Turkish tree several weeks ago and my subjective estimation is that my vocabulary, grammar, reading comprehension, and writing are definitely beyond A1 (as defined here). I think, with some extra exercise, all these skills can be brought to at least A2 using Duolingo only (and some program or service to train vocabulary, because "Words" section is missing in all community-created courses). My listening comprehension is A1, because of lack of practice and Duolingo is definitely not enough to improve it. As to the amount of grammar provided by the course, I assume that it is enough for B1 or even B2.