1.？ Classification of research fields. According to research fields and majors, such as literature, history, psychology, education, economics, etc.
2.？ Classification of research methods. According to different research methods, it can be divided into empirical research, literature review, philosophical analysis and case study. Each method has its own special research paradigm and requirements.
3.？ Research topic classification. According to research topics and problems, such as social phenomena, science and technology, cultural communication, environmental protection, etc.
4.？ Classification of research objects. Classify according to research objects or cases, such as policy research at the national level, research on institutions and organizational forms, and research on individual subject behavior.
In the actual writing process, we need to choose appropriate classification methods to organize the content of the paper according to our own research topics and purposes, so as to make it clearer and more logical.