1. A speech communication system enabling a conversation with a conversation partner, said system comprising: a speech recognition unit configured to recognize a speech content of the conversation partner; a conversation control unit configured to continue the conversation using available resources; an image recognition unit configured to recognize a face of the conversation partner; and a tracking control unit configured to, in a normal mode, track a position of the conversation partner in response to both of a recognition result of the image recognition unit and a recognition result of the speech recognition unit, wherein while the speech communication system is in a failure mode as a result of an inability of the tracking control unit to track the position of the conversation partner, the conversation control unit is configured to continue the conversation without tracking including behaviors relying, in the normal mode, on tracking performed by the tracking control unit, the conversation is continued, without tracking, through the speech content of the conversation partner being recognized with the speech recognition unit and matching a predicted response.