Confidence in translating text
Sometimes I'm really not sure what a text is trying to say, but I do my best anyway. Other times, clues come together and it clicks and I know what they're talking about. Duolingo may make me lose a heart but I really know other people are wrong! It would be nice to be able to say that I'm really confident, or not confident at all, in my answer.
Also, sometimes I only figure out what a title is about after a read a few sentences of the article. Then, I have to go back to change my answer -- it would be nice if I could edit old answers. Also, often, going to the original site is necessary to get context and see the pictures in their places.