Current linguistic theories, such as interpretive and generative semantics, are judged theoretically unsound and practically unsuitable for pedagogical purposes. Although the concept of case must be included in a grammar, current case theories are also rejected. The concept of case is redefined, as are the defining criteria for each case. A noun is said to be case-marked only if it can fill the subject, indirect object, direct object, or range positions in a given sentence. All other nouns in a sentence are adjuncts. Every verb is marked for the cases with which it appears, and the beginning of the generation of a sentence is the selection of a verb and its cases. Details of the cycle for generating a sentence, including lexical selection, semantic interpretation, and sentence embedding, are presented. Deviant sentences taken from freshmen themes are examined in the light of this model. The final chapter of this research study shows how abstract linguistic theory can be used in a practical program for teaching rhetoric. (Author/DI)