something i've noticed, and its usually when answering speaking tests, is that it often does not tell you what the sentence means. for example you may do a speaking test and you may word it correctly and pass the test, but you didnt know what one of the words or the sentence meant.
I feel it would make a big difference to the learning experience if you were also given the translation just incase you did not know the meaning of the sentence or a word. Otherwise it simply passes you, gives you no translation and you are forced to continue to the next question without knowing the meaning of the sentence. (You simply knew how to pronounce it.)
If anyone else has noticed this and feel it would help to have the translation, comment here :) hopefully duo staff will take note.
But i would like to say a gracias grande! to the Duolingo staff for this amazing software its incredibly well designed. love it.