JoomlaLMS has a Forum tool for easy communication between the course participants on different course issues. The course Teacher is a moderator of this forum by default. The course Teacher decides to enable forum for the course and course item or not and the Teacher is a moderator of this forum by default. To activate the course Forum the Teacher should check the Yes box in the New course creation form (see Courses List chapter). The Teacher can add forums for quizzes too. This is how the Forum board looks:
The forum Administrator manages this board. Here the course Students can share their ideas with the Teacher and other Students and comment the course. It's possible to organize group forum too (to learn how you can enable group forum, refer to the Creating User Groups topic). It operates as any usual forum so it won't make any difficulty to use this tool. Post messages, manage your profile and posts, ask the Administrator for help using corresponding tabs at the top.