I'd also agree with using the raise hand function to post comments or to answer your questions. when there is a direct question about our opinions or something, you could say the name of the person raising his/her hand and only this person is allowed to write in the chat. that would be closest to the situation of a real classroom, I believe. It really was such a pity as there were about 20 people answering your questions at the same time, and most of it got lost because of the sheer amount of it. so very good comments might not be registered and only the ones who can type fastest or incidentally post their comment at last, so that it will be seen for a while. i think that this is quite discouraging, as you must always expect that your comment isn't noticed properly.