Ordinary university teachers go from teaching assistants to lecturers, associate professors and professors, not because they have taught for many years, but because they have research value. Basically, teachers above associate professor have done national, provincial and municipal scientific research projects, and each project has funds, and the rest of the money after the project is completed is theirs. Moreover, if their projects are well done, there will be bonuses, and there will be bonuses after the awards. Many university teachers have social part-time jobs, such as lawyers, part-time engineers in an enterprise, corporate consultants and so on.