1. A speech processing apparatus which generates guidance speech corresponding to user operation using a speech synthesis unit configured to perform speech synthesis while selectively changing recorded-speech-playback and text-to-speech, the apparatus comprising: a guidance holding unit that holds (i) a first guidance including fixed portions indicating fixed messages, and a first variable portion, and a second variable portion, wherein the first variable portion and the second variable portion are located between the fixed portions and indicate that a first message and a second message corresponding to user operation are inserted, (ii) a second guidance that has the second variable portion located at the end of a fixed portion and is synonymous with the first guidance, and (iii) a third guidance which has the first variable portion located at the end of a fixed portion and is synonymous with the first guidance; an entry holding unit that holds a set of entries in which spellings, pronunciations of the spellings, and pieces of speech based on the pronunciations which are associated with user operation are configured to be registered; and an acquisition unit that acquires an entry corresponding to operation performed by a user from said entry holding unit, wherein, based on a number of times of changing between the recorded-speech-playback and the text-to-speech when performing speech synthesis, said speech synthesizer unit applies: the first guidance if the number of times of changing when performing speech synthesis using the first guidance is less than a predetermined number, the second guidance if the number of times of changing when performing speech synthesis using the first guidance is not less than the predetermined number, and if the number of times of changing when performing speech synthesis using the second guidance is less than the predetermined number, and the third guidance if the number of times of changing when performing speech synthesis using the first guidance is not less than the predetermined number, and if the number of times of changing when performing speech synthesis using the second guidance is not less than the predetermined number, and if the number of times of changing when performing speech synthesis using the third guidance is less than the predetermined number.
2. The apparatus according to claim 1 , further comprising: a communication unit configured to perform network communication, wherein the user operation includes an operation associated with network communication, and wherein said entry holding unit comprises an address book for network communication.