Various communication methods have been introduced in public involvement process of transportation infrastructure project in recent years. Regarding public meetings, which is one of the most important public involvement techniques, we often struggle to build relationships and communicate information with citizens. For example, by giving an ambiguous reply at the question, it may encourage civic anxiety and dissatisfaction, which may adversely affect the progress of subsequent projects. Therefore, in this research, we define "periphrasis" as one of the characteristics of response posture and consider how to respond with persuasive power. Then, we pay attention to explanatory procedure of response. We produced several response voices considering the above factors and surveyed by web questionnaire evaluating those response voices. By examining the result, we obtain knowledge about effective oral communication in the question and answer scene.