An accurate repertoire of tacts and intraverbals about behavior is essential for scientific and technical communication. All behavioral effects of the environment can be classified in an eight-cell arrangement created by three dichotomies: respondent versus operant, evocative versus function altering, and unlearned versus learned. By refining some old definitions and inventing a few new terms and symbols, it becomes possible to locate any functional relation in the eight cells of this set of categories. Much instruction about behavior analysis can then focus on helping students master a two-part repertoire consisting of (a) providing the term (or symbol) when given a description of a relevant situation and (b) describing the environmental and behavioral evidence for the relation when given the term (or symbol). This system of analysis is described and illustrated with sample questions and answers that teach about the system.