An OT Approach To The Directionality Of Chengdu Tone Sandhi

The directionality of tone sandhi in many Chinese dialects has remained a heated topic and unsolved problem. However, previous analyses of this topic have been proved to be problematic. This thesis presents an OT (Optimality Theory) approach to this issue and tries to offer a better solution to the problem. From the perspective of OT and tonal theories, and based on Chengdu dialect data, this thesis attempts to investigate the phenomenon of Chengdu disyllabic and trisyllabic tone sandhi, trying to capture the phonological motivation and mechanism which configure disyllabic and trisyllabic sandhi forms in Chengdu dialect.The observation of Chengdu disyllabic tone sandhi tells us that it is usually the right syllable undergoes tonal change, rather than the left one, which is different from the sandhi phenomenon of Beijing Mandarin. The directionality of trisyllabic tone sandhi is unpredictable because sometimes the direction is left-to-right and sometimes right-to-left, which cannot be explained by morpho-syntactic structure, either. The present study suggests that different direction will lead to different application modes: when the sandhi direction is right-to-left, the output undergoes underapplication, and when the direction is left-to-right, the output undergoes normal application. The motivation of different direction is to satisfy correspondence between base tone and output tone, and this is why certain sandhi forms undergo underapplication-to satisfy the Base-Output-Identity correspondence. Naturally, the faithfulness constraint Identity-Base-Output-Tone can capture this correspondence. However, certain forms will lead to output tones violating highly-ranked markedness constraints when they are trying to satisfy Base-Output correspondence, and then sandhi will turn to the opposite direction. Therefore, the directionality of Chengdu trisyllabic tone sandhi can be predicted by the interaction between faithfulness constraints and markedness constraints.This thesis consists of five chapters. Chapter One introduces the significance of present study and the organization of the thesis. Chapter Two introduces the Chengdu dialect and provides some data, mostly the citation tones, the disyllabic and trisyllabic sandhi forms. Chapter Three is the introduction of theoretical backgrounds, including OT and allomorph generation and selection. Chapter Four, focusing on the technical analysis, makes an analysis of Chengdu disyllabic and trisyllabic tone sandhi from the perspective of OT. Chapter Five overviews the previous study on this topic and makes a comparison between previous study and present study. Chapter Six presents a conclusion.