| Based on the theoretical framework of functional grammar, this article focuses on the semantic evolution and pragmatic functions of the "ding" class of adverbs in Chinese, addressing the unresolved issues in previous studies regarding the grammaticalization path of "ding（定）", the comparison of related morphemes, and the interaction with context. The article examines the diachronic evolution of "ding" from the Pre-Qin period to the Qing Dynasty, revealing its complete grammaticalization transformation and the derivation of disyllabic forms such as "yiding(一定）", "biding（必定）", and "ken ding（肯定）", with the internal differences resulting from the diachronic interaction of morphemes like "yi（一）", "bi（必）", and "ken（肯）". At the modal function level, this class of adverbs dynamically constructs a three-part system of dynamic, deontic, and epistemic modality through syntactic structures such as "X ding yao（X定要）" and "X ding hui（X定会）"; at the pragmatic level, it manifests functions such as implicit information transmission markers, focus highlighting, interpersonal interaction, and textual cohesion. The article aims to provide a reference for the systematic study and standardized application of modal adverbs in Chinese. |