Then there are the contents and materials of the course, which are developed by the students themselves. I don't know whether it is allowed because I didn't pass the exam. But one thing I want to vomit is that because they are all online video courses, there are many people asking questions when the teacher is in class, and your questions will soon be brushed away, and the teacher can't see them, and the staff can't answer you in time, so any questions should be raised in time, but the effect of the class is not necessarily good.