The transduction of a small set of internally represented ideas into written or oral text is in an obvious sense the inverse of the understanding process, as we have outlined it in the preceding sections 2–5. In other words, starting from a few internally represented ideas to be communicated, we need to proceed to an orderly linear arrangement of these ideas, to a surface-oriented logical form that is concise and nonrepetitive and appropriately indexical (e.g., in the use of I, you, here, now, and referring expressions), and finally to an actual surface realization and physical presentation of that realization as spoken or written text. Most or all of the kinds of knowledge involved in understanding naturally come into play in generation as well—whether the knowledge is about the structure of words and phrases, about the relationship between structure and meaning representation, about conventional (or creative) ways of phrasing ideas, about discourse structure and relations, or about the world.