Speech synthesis in unbounded words becomes more and more important today. I want to suggest two reasons for that phenomena. The first reason is to bring out better relationship between machine, especially computer and human. The second is to process informations faster and more efficiently. Speech synthesis in limited words is very different with that in unbounded words. We must modify the sound, especially the tone of voice in unbounded speech synthesis owing to ths limited size of machine memory. In this paper, I treat two parts. One is a global speech synthesis system and the other si the pitch control of sound, which is the essential of unbounded speech synthesis