Title: Topic structure and sentence semantics
In recent years, there is a trend among functionally oriented scholars of Chinese linguistics to establish distinctive functional/semantic principles of grammatical organization for Chinese, with the belief that the English-type of clause structure is essentially at odds with the facts in Chinese. In this attempt, the traditional assumptions about grammatical units and constituencies are also thrown into question. Various properties of Chinese grammar are suggested as evidence, such as pragmatically oriented word order, loose syntactic organization and the influential "topic prominence". This paper reviews some aspects of these arguments and their implications as relating to a functional approach to Chinese sentence grammar, especially the Functional Component Hypothesis of the mainstream Systemic Linguistics. It will be proposed that three functional layers hierarchically organize the basic unit in Chinese grammar, the topic-comment structure being the highest layer, which, like the other two layers, are open to but independent from the textual packaging of syntax.