Help and questions What is a course “session” at CLL? A session at CLL is a cycle of courses of between 20 and 40 hours, divided into 10 to 20 lessons of two to three hours each. Was this article useful? Other related questions What happens if I am miss one or more lessons? How do I choose a course adapted to my needs? Should I enrol in a course that corresponds to my current level or to the level that I want to achieve?