Comparatively, literature is a cross-disciplinary literary discipline that includes many different schools of thought. The following are some of the main schools of thought and their main research methods: 1. Historical School: This school emphasized the historical status and significance of the study of literature by comparing literary phenomena in different cultural, historical, and social backgrounds. The research methods of the historical school included in-depth study of literary works and investigation of historical background. 2. The School of Culture: This school focuses on the cultural factors behind literary works and probes into cultural differences and commonalities by comparing literary phenomena between different cultures. The research methods of the cultural school include the in-depth study of cultural factors and the cross-cultural interpretation of literary works. 3. School of Language: This school focuses on the language of literary works and the meaning of language use. By comparing the literary phenomena between different languages, it probes into the differences and similarities of languages. The research methods of the School of Language included the in-depth study of language structure and the analysis and interpretation of the language used in literary works. 4. The School of Society: This school pays attention to the influence and significance of literary works on society. By comparing literary phenomena in different social backgrounds, it probes into the influence and role of literature on society. The research methods of the sociological school included the in-depth study of social history and the analysis and discussion of the relationship between literary works and society. The study methods of comparison literature include cross-cultural interpretation of literary works, language analysis, cultural comparison and social development. The research focus and methods of these schools may be different, but in general, it is an inter-disciplinary discipline.