To provide a speech synthesis apparatus which can prevent user confusion and deterioration of the quality of synthesized speech resulting from incompleteness of the sentences to be read out, and thus can read out speech which is easily understandable to the user. The speech synthesis apparatus includes: an incomplete part-of-sentence detection unit which detects incomplete parts-of-sentences which become linguistically incomplete because of the presence of a missing character string and which complements the detected incomplete parts-of-sentences having a missing character string, with reference to the e-mail texts which have been received by and accumulated in a mail box; a speech synthesis unit which generates synthesized speech based on the complemented e-mail texts; an incomplete part-of-sentence obscuring unit which obscures the acoustic clarity of the synthesized speech corresponding to the incomplete parts-of-sentences detected by the incomplete part-of-sentence detection unit; and a speaker device which plays back and outputs the generated synthesized speech.
Speech synthesis system for naturally reading incomplete sentences