Projection and retrospection are the two primary factors in understanding how talk-in-interaction is structured in real-time. Powerful resources to mark a projective or retrospective relation between turns include conjunctions, and the contrastive conjunction kedo ‘but,’ which can be used in both turn-initial and turn-final positions, is one of the most prominent devices in Japanese conversation. Focusing on the cases where turns with kedo are used as responses to the prior turn of the interlocutor, this study compares the interactional functions of the turn-initial and turn-final kedo. Through detailed analysis of excerpts taken from the Corpus of Everyday Japanese Conversation, it is shown that while both turn-initial kedo and turn-final kedo are similar in that the speaker presents his or her own turn as more or less contrasting to the preceding turn, they differ in the typical sequential contexts and the subsequent trajectories of the interaction. Specifically, kedo-prefaced turns are used to bring in a new perspective and thereby project a sequence dealing with the newly introduced perspective. By contrast, kedo-ending turns do not invite further topical development but provide a supplementary comment retrospectively on a prior part of the conversation.

预测和回顾是了解如何实时构建互动对话的两个主要因素。标记转折之间的投射或回顾关系的强大资源包括连词，对比连词kedo 'but' 可用于转开头和转结束位置，是日语会话中最突出的设备之一。本研究针对使用kedo的转弯作为对对话者先前转弯的响应的情况，比较了转弯初始和转弯kedo的交互功能。通过对从日常日语会话语料库中摘录的节选进行详细分析，可以看出，虽然和回合结束kedo的相似之处在于说话者将自己的回合或多或少地与前一个回合形成对比，它们在典型的顺序上下文和随后的互动轨迹上有所不同。具体来说，以kedo开头的转折被用来引入一个新的视角，从而投射一个处理新引入的​​视角的序列。相比之下，kedo结尾的转折不会引起进一步的话题发展，而是回顾性地对对话的前一部分提供补充评论。