To me, Duolingo is one of the worst resources for Russian language. Just out of interest, i wanted to take a look at Duolingo, and already found lots of mistakes at the very beginning of their courses. Actually i don't remember what it is called quiz or course whatever the hell, but you got what i meant.
If you want to practice, i strongly encourage you to find a native speaker friend or at least someone who is fluent in Russsian, preferably someone who lives or already lived for a long time in a Russian speaking country.
