The thing is that I don't always completely agree with the answers given in the course, and I can see no way to discuss them, since only the lesson itself gives the opportunity to send comments. Suggesions?
Our teacher is a robot which grants nothing but questions it has itself planned. As have already done some fellow-GGusers, you may jot down this forum in "English language forum" heading the perplexing issues.
You can write down any specific questions you have here in the forum! Be specific, though!