新支话题的句法成分和语义角色研究

话题的延续和转换是篇章中重要的语用功能。该文从句首话题共享的角度对话题延续和转换进行了分类,分为句首话题延续、句中子话题延续、完全话题转换、兼语话题转换、新支话题转换五种,进而对话题转换的特殊情况——新支话题展开研究。基于33万字的广义话题结构语料库,该文对新支话题的句法成分、语义角色进行了统计和分析。通过句法成分分析发现,宾语从句或补语从句主语、主谓谓语句小主语、状性成分起始句主语、句末宾语、连谓句非句末宾语、兼语句兼语、介词宾语甚至状语等都能成为新支话题,从而引出新支句,其中,句末宾语作为新支话题的情况最多,但未发现间接宾语作为新支话题的情况;语义角色分析发现,大部分主体论元(施事、感事、经事、主事)和客体论元(受事、系事、结果、对象、与事)及少数凭借论元(方式)和环境论元(处所、终点)能成为新支话题引出新支句。同时,系事和受事成为新支话题的情况最显著;施事、结果和对象次之;原因和目的等论元难以成为新支话题。该文的研究揭示了句法、语义对话题转换这一语用现象的一种可能的约束途径,有助于人和计算机更深入地理解汉语篇章的话题转换机制,以期将这种语用现象逐步落实到语义直至句法的形式中,最终实现计算机对话题转换的自动分析。

A Study of Syntactic Constituent and Semantic Role of New Branch Topic

Topic Continuity and Topic Shift are important pragmatic functions in discourse. From the perspective of topic sharing at the beginning of a punctuation clause (P-Clause), this paper classifies the Topic Continuity and Topic Shift into five categories: Topic Continuity at the beginning of a P-Clause, Sub-topic Continuity among a P-Clause, Completely Topic Shift, Pivotal Topic Shift and New Branch Topic Shift. Then focusing on the New Branch topic, we conduct a statistic analysis of the syntactic constituents and semantic roles of the New Branch topic based on a corpus of Generalized Topic Structure with 330, 000 characters. As for syntactic constituents, the subject of an object clause or a complement clause, the small subject of a sentence with S-V structured predicate, the subject of an adverbial starting sentence, the object at the end of a sentence, the object of a co-verbal sentence, the pivot of a pivotal sentence, the prepositional object, and even the adverbial can serve as New Branch topics, which introduce one or more New Branch clauses. Among them, the object at the end of a sentence is the most frequently used as a New Branch topic, but no indirect object was found to be a New Branch topic. As for semantic roles, most of subject arguments (agent, sentiment, experiencer, theme) and object arguments (patient, relative, result, target, dative) are found to be New Branch topics. As for the supporting arguments (manner) and environment arguments (location, goal), a few of them can function as New Branch topics and lead to New Branch clauses. Among them, relative and patient are the most typical New Branch topics, followed by agent, result and target, but cause and aim can hardly function as New Branch topics. Our study reveals a possible path for syntactic and semantic constraints on Topic Shift.