Yes it does. However, from when I’ve used Duolingo, all that was theory. There is no application of the language in conversation. In Busuu, the app asks you to apply what you’ve learned by having you write a few words or sentences as review. What you write is sent to and corrected by native speakers. Duolingo might teach u the different forms of “to be", but never has you apply it the way other methods like HelloTalk and Busuu do.