Based on a case study of the evolution of "finish" morphemes in Yue and Zhuang Tai-Kadai, this book examines how an internal factor (grammaticalization) and an external factor (language contact) interacted to produce the polyfunctionality of the specific "finish" morphemes in the languages of Guangxi Zhuang Autonomous Region, Southern China. Arguing that the Central Southern Guangxi Region is a micro-linguistic area, Huang also introduces five unique areal features shared by many of its languages.