Abstract: A sentence forming apparatus forms a plurality of semantically equivalent sentences simultaneously in a plurality of languages by a conversational system. The apparatus includes a semantic dictionary memory which stores a plurality of indexes in a first language, a plurality of words in the first language semantically in coordination respectively with the indexes and grammatical information relating to the respective words, and first language syntax dictionary memory and second language syntax dictionary memory which store information concerning grammatical syntax and word in the corresponding language. A selection menu is formed based on the contents of the semantic dictionary. The apparatus further includes first language sentence assembler and second language sentence assembler which assemble, respectively, the first language sentence and the second language sentence utilizing the information concerning the grammatical syntax and word in the respective languages, in accordance with the selection menu.