33. The method of claim 21, wherein at the generating step, the speech response for making a confirmation of the input speech is generated, the speech response being changed from a full speech response to a simplified speech response, according to a length of the speech response for making the confirmation.
21. A method of speech dialogue between a human user and a speech dialogue system, comprising the steps of: understanding an input speech from a user; determining a response output according to the input speech; generating a speech response and a visual response according to the response output; and outputting the speech response and the visual response generated to the user.