Human discourse is fraught with rhetorical devices such as contradictions, illustrations, and analogies. These rhetorical devices carry important information which a listener uses to speed up the comprehension process. In this paper, we present a taxonomy of rhetorical devices commonly used in tutoring environment, and model the meaning of a class of rhetorical devices in terms of their anticipated effect on a listener's knowledge. These predictions are then used in planning computer‐generated discourse. As a testbed for our ideas, a system called WISHFUL is being implemented to generate commentaries in the domain of high‐school algebra within the framework of an intelligent tutoring sys