There is no question of the value of applying automatic speech recognition technology as one of the interaction tools between humans and different computational systems. There are many books on design standards and guidelines for different practical issues, such as Gibbon's book Handbook of Standards and Resources for Spoken Language System (1997) and Handbook of Multimodal and Spoken Dialogue Systems: Resources, Terminology and Product Evaluation" (2000), Jurafsky's Speech and Language Processing (2000), Bernsen, et al.'s book Designing Interactive Speech System (1998), and Balentine and Morgan's book How to Build a Speech Recognition Application - A style Guide for Telephony Dialogues (2001), etc. Most of these books focus on the design of the voice itself They provide certain solutions for specific dialogue design problems. Because humans are notoriously varied, human perception and human performance are complicated and difficult to predict.