30. A method according to claim 28, wherein said parameter determining step includes a person determining step for determining the person mentioned in the selected natural language expression selected in said selecting step.
28. A natural language processing method for processing internal conceptual expressions of a computer not in a natural language so that they are converted to a message in a natural language in accordance with the expression form of the message determined to be preferred by a person intended to receive the message, comprising: an input step of inputting information expressed by a list of concepts each comprising an internal conceptual expression of a computer not in a natural language that is to be communicated to a person intended to receive a message embodying the concept; a linguistic concept generating step for generating a linguistic concept dependent upon language to be added to individual concepts in the list of concepts input in said input step; a parameter determining step of determining a parameter for the linguistic concept generating in said linguistic concept generating step; a selecting step of determining the expression form of a message embodying the individual concepts preferred by the person intended to receive the message by using the individual concepts, the determined parameter, and data in a knowledge base having the knowledge of natural languages, general knowledge, and the knowledge of specific domains, said selecting step selecting one natural language expression form of the message from a plurality of possible expression forms embodying the individual concepts in accordance with the determined, preferred expression form of the message; and a conversion step of converting the individual concepts into the message embodying the individual concepts in a natural language expression selected in said selecting step.