The Discourse Markers in Coherence Relations

The role of discourse markers in discourse coherence is an important topic in linguistic research, but there is diversity and a lack of unity in existing classification frameworks. In this study, through the literature review method, we systematically sort out the classification frameworks proposed by Fraser, Schiffrin, Redeker and other scholars and compare the functional similarities and differences of DMs in different languages, aiming at integrating the existing theories in order to reveal their core roles. It is found that the core function of discourse markers is procedural orientation, which achieves coherence by connecting discourse units, and their classification can be categorized into semantic-functional and discourse-management types; cross-linguistic studies show that discourse markers in different languages differ significantly in terms of their functional distributions and formal correspondences, and that the diversity of classifications stems from the multidimensional interactions of discourse markers at the syntactic, semantic, and discursive levels. This study concludes that the multiple classifications of discourse markers reflect the dynamic complexity of their discourse organization, and future research needs to build a more inclusive theoretical framework by combining the formal and functional perspectives to provide an integrated path for the systematic analysis of discourse markers, while emphasizing the importance of cross-linguistic comparisons for an in-depth understanding of their nature.