In the exercise entitled "A Book Lover," there is a phrase "...rien qu'en observant ses grands frères et sœurs." When I gave exactly that spelling, the s's at the end of "frère-" and "sœur-" were marked as incorrect...even though they were present in the correct example, and the narrator gave us a very clear clue that the words were plural by the way she pronounced "ses." Just letting you know about this glitch in the program.
Also, I frequently find myself needing a 2nd or 3rd listen to be certain about certain words. Sometimes I'm able to get the program to repeat the recording, often not; when I do, I often need to click on the audio button multiple times before it complies. Either I'm trying to cheat, or the function allowing us to hear the phrase over again doesn't work very well. Please let me know which is the case!
Otherwise, I'm enjoying these challenges very much!