I can answer this question. Zhong Qian is very formal. I took the clinical practice exam last year and signed up for his class. I passed the exam in a year. However, I personally think that class registration is only an auxiliary means. It will be much easier to have a teacher explain where you can't, but you still have to rely on our personal efforts to review. If you can't sign up for class, you won't learn much. Master leads the door, and practice depends on individuals!