This paper describes the use of an on-line system to do word-sense ambiguity resolution and content analysis of English paragraphs, using a system of semantic analysis programmed in Q32 LISP . The system of semantic analysis comprises dictionary codings for the text words, coded forms of permitted message, and rules producing message forms in combination on the basis of a criterion of semantic closeness. All these can be expressed as a single system of rules of phrase-structure form. In certain circumstances the system is able to enlarge its own dictionary in a real-time mode on the basis of information gained.