they are available in all schools.

students from every school can attend better and better training courses. There is no requirement that designated students attend the training class.

from the training intensity, it can be divided into primary training courses, intermediate training courses and advanced training courses. From the economic point of view, it can be divided into commercial training courses and compulsory training courses. From the perspective of scale, it can be divided into small training courses, neutral training courses and large training courses. In terms of popularity, it is divided into. Popular training courses, unpopular training courses. From the formal point of view, it is divided into: traditional training courses and online training courses.