本文旨在研究话语标记在话轮转换中的功能。话语标记是一种日常交谈中常见的语言现象。近些年来，话语标记因其广泛的功能性引起了众多学者的关注。学者们把关注的焦点多放在个别话语标记的个案语用分析上，而从话轮转换的角度对话语标记功能的研究却很少。话轮是会话分析理论的核心议题；过去学者对话轮的构成、分配以及转换规则的研究为本文提供了理论基础。 本文希望能够对话语标记如何帮助说话者实现话轮转换的问题作出回答。在本文中，我们回顾总结了前人对话语标记、话轮转换以及脱口秀节目的研究成果，并描述了萨克斯等人提出的话轮转换理论作为本文的理论框架。之后我们重点分析了美国著名脱口秀——奥普拉秀一期节目中发生的会话，并发现话语标记确实在话轮转换行为中起了十分重要的作用。按照话语标记在话轮转换中起到的功能的不同，众多话语标记被分成三类：起始话轮，保持话轮，放弃话轮。本文列举了大量语料中的实例，以阐释话语标记在会话中的具体功能。最后，本文结论认为话语标记在保持话轮和起始话轮中使用频率较高，功能也多种多样，在放弃话轮行为中虽然不如前二者，但话语标记仍然是实现放弃话轮的手段之一。

The present study is carried out to find out the functions of discourse markers from the perspective of turn-taking in conversation. Discourse markers are widely used in daily conversation. In recent years they have attracted much attention because of their multifunction. However, the function of discourse markers has rarely been deep explored from the perspective of turn-taking. Turn, which is a crucial issue in Conversation Analysis, has been analyzed in detail in previous studies as to the construction, the allocation and the rules of turns. This thesis is trying to show how discourse markers work in helping the speaker achieve turn-taking in conversation. Through a thorough analysis of the conversation taking place in an episode of Oprah Winfrey show, the paper comes to the conclusion that discourse markers do play an important role in turn-taking behavior. The analysis is generally based on the review of the previous studies on discourse markers, turn as well as talk shows, and framed in the theory of turn-taking. In the analysis, discourse markers are classified into three categories according to their functions: turn-claiming, turn-holding and turn-yielding. A number of examples are presented to illustrate how every discourse marker functions in turn-taking behavior. Thus at the end of the thesis it is concluded that discourse markers are very commonly employed in turn-claiming and turn-holding; to turn-yielding they do not contribute as much, but their functions are ignorable, after all.