Semantic Distribution and Diachronic Development of Deontic Modality in Taiwanese Hakka: A Corpus-Based Constructional Approach

This study aims to establish a systematic analytical framework for deontic modality in Taiwanese Hakka. By drawing on corpus data and statistical methods, it provides empirical evidence for the functional differentiation and diachronic development of the modality system. At the descriptive level, the study clarifies the semantic distinctions and usage conditions of different modal markers, and reveals their distributional patterns across various contexts. At the theoretical level, it adopts a constructional and grammaticalization perspective to account for the division of labor and developmental mechanisms of modal markers within the constructional network, while also evaluating the multiple-source hypothesis. Methodologically, the study demonstrates how quantitative approaches can be integrated to analyze semantic and syntactic variation, thereby enhancing the objectivity and replicability of linguistic research. In addition, the findings are expected to contribute to Hakka language pedagogy, language preservation, and language technology, and to make a meaningful contribution to the study of local languages in Taiwan.