SENTENCE SEGMENTATION METHOD AND SENTENCE SEGMENTATION APPARATUS, MACHINE TRANSLATION SYSTEM, AND PROGRAM PRODUCT USING SENTENCE SEGMENTATION METHOD

To provide a highly accurate sentence segmentation process in natural language processing by estimating parts of speech of words in text to be processed. Dictionary data is used to perform a sentence segmentation process on a text to be processed. If it cannot be determined through a user of the dictionary data whether the text should be broken into sentences, the parts of speech of words constituting the text are estimated and a further sentence segmentation process is performed based on the result of the estimation.