Abstract: A pattern matching rule for recognizing a weakly linked idiom is previously held in a pattern matching section. If a weakly linked idiom which is registered in the pattern matching rule and has separately placed portions is present in an input sentence, the pattern matching section recognizes the idiom. If the weakly linked idiom is recognized by the pattern matching section, the idiom is replaced by a series of symbolized pattern expressions in a replacing section. A sentence subjected to the replacement process in the replacing section is given to an analyzing section. The analyzing section treats the series of symbolized pattern expressions as one idiom and analyzes the sentence. As a result, the result of analysis in which the weakly linked idiom is adequately processed is obtained as an output of the analyzing section.