Sentence creation apparatus and creation method

A sentence generating method and apparatus for generating a joke sentence set having a dual meaning. A predetermined word in a selected first idiom is stored in a W list. A word of analogous sound having the pronunciation same as or analogous with the word in the W list and also being of the same word class as the word in the W list is stored in a RW list. It is then checked whether or not the subject word stored in the P list has a semantic relationship with the word of the analogous sound in the RW list. If the result of check is affirmative, a first joke sentence having the subject word in the P list and composed of the subject word of the P list and the first idiom is generated. A second idiom, corresponding to the first idiom, in which the word in the W list is replaced by the word of the analogous sound in the RW list, is generated, and a second joke sentence composed of the subject word of the P list and the second idiom is generated.