Patent ID: 6862566

Claim:
An expression converting method wherein by use of classing information in which key words are previously classed based on predetermined properties and each class Is provided with a name, for each sentence in a corpus, key words are selected from the sentence, a combination of classes that are in a co-occurrence relation are identified from among a predetermined number of combinations of classes among classes to which the selected key words belong, and the Identified class combination and an expression into which the sentence from which the key words are selected is converted are previously associated, and wherein predetermined key words are selected from an input sentence, classes to which the selected key words belong are combined, the class combinations and the previously identified class combination of each sentence are compared, one or more than one sentences that coincide or have a high degree of similarity as a result of the comparison are selected, and expressions into which the selected sentences are converted are output, and the predetermined key words of each sentence in the corpus are stored, from the stored predetermined key words of each sentence in the corpus, predetermined class combinations of key words are selected as having a dependency relationship and stored, and the predetermined class combinations of key words are Individually selected for each sentence from the stored predetermined key words of the sentence.