We have already confirmed the importance of embodied sharing in avatar-mediated communication and have demonstrated the effectiveness of the entrained nodding responses for human interaction and communication support. In this paper, in order to support the avatar-mediated communication, a virtual audience system is developed by using a speech-driven embodied entrainment picture in which interactive CG objects behave as listeners such as nodding responses. This system provides a communication environment in which not only avatars but also the CG objects placed around the avatars are related to embodied communication. By using this system, the effectiveness of the present system in supporting embodied communication has been demonstrated by carrying out a sensory evaluation and a speech-overlap analysis for 20 pairs of 40 talkers.