Voice answer always correct
For every answer where I answer in the microphone I get that the answer is correct. Even if I click fast on and off on the microphone button does it say I was correct.
I realized one day that I could say something ridiculous like "Three blind mice" and Duo would count it as correct.
I turned off my microphone (you can do this in "settings") and now every time Duo says a sentence or a phrase, I repeat it a few times, then I say it along with Duo. Sometimes I copy-and-paste the sentence into Google Translate and say it along with that voice.
I have found that this helps me with my pronunciation and rhythm a lot more than the Duo exercises ever did. It's not my own idea; someone else on Duo suggested it and I gave it a try and found that it really works well.