15. The information processing system according to claim 4 , the circuitry further configured to associate a plurality of expressions expressing the same or similar actions or environments with a typical expression which is a typical expression of the plurality of expressions, and stores the associated expressions; and refer to the stored typical expression, on the basis of the environment expressions or the action expressions, to replace the environment expressions or the action expressions with the typical expression.
4. The information processing system according to claim 2 , the circuitry further configured to associate an action expression with an environment expression extracted from the same incident information.