New words in practice session.
Sometimes when I practice all the skills so far (the bubble on the left) I am getting words that I haven't seen before - they were never shown while learning. It's sort of ok because I can peek and see the translation but I don't think it is supposed to do this.
Also word practice is quite limited. I see plenty of Lehrer, Frau, Mann, Madchen, trinken, essen & very basisc but rarely other words I learned before.
I've picked up a ton of German by looking up those words not formally introduced here. I like them, since it breaks up the monotony of Lehrer, Frau, Mann, Ente, and those irritating Sandwiches. I think Duolingo limits the vocabulary, with German, because they focus on the structure of this language which is very complex. If you want new words, got to Memrise which is an excellent interactive vocabulary builder. I use that for words, Duolingo for structure.