Generating Understandable Explanatory Sentences

An important component of a language generation system is being able to produce explanatory sentences and texts. Operationally an explanatory sentence can be defined as a sentence which is an appropriate answer to a why-question: (1) Q: Why did John go out? A: He wanted to buy a packet of cigarettes Explanatory talk, of course, goes beyond producing appropriate answers to why-questions. What we may also want to call explanations are responses to requests for definition and clarification of terms, concepts, or ideas, or to questions about conclusions reached, methods followed, and so forth — all of which are usually not formulated as why-questions. Howewer, for the purposes of the present paper, we will restrict our attention to giving explanations as answers to why-questions.