A method which includes performing a structure analysis on a natural sentence inputted by making use of a word dictionary DIC-WD and a configuration dictionary DIC-KT and converting letter series KNJ of the inputted natural sentence into a language structure information series IMF-LSL. The natural sentence inputted in the form of the language structure information series IMI-LSL is subjected in such a manner to application of meaning analysis grammar IMI-GRM to cause a single or a plurality of meaning frames IMF-FRM to be read out from a meaning frame dictionary DIC-IMI in accordance with commands of the meaning analysis grammar IMI-GRM. When a plurality of meaning frames IMI-FRM are read out a meaning frame which defines an abstract meaning expressed by the inputted natural sentence is synthesized by case coupling and/or logic coupling the meaning frames IMI-FRM. Words WD, particles JO and symbols KI are inserted into the meaning frames IMI-FRM read out or the meaning frame IMI-FRM synthesized to thereby determine and produce data sentence DT-S correctly expressing the meaning of the inputted natural sentence in a computer whereby the language structure information series IMF-LSL is converted into the data sentence DT-S in the form of data structure PSMW with a multi layered case-logic language structure.
Natural language processing method for converting a first natural language into a second natural language using data structures