It is widely recognized that a question-answerlng system should be able to tailor its answers to the user. One of the dimensions Mong which thus tailoring can occur is with respect to the level of knowledge of a user about a domain. In particular, responses should be different depending on whether they are addressed to ns/ve or expert users. To understand what those differences should be, we a~alyzed texts from adult and iunior encyclopedias. W e found that two different strategies were used in describing complex physical obiects to juniors and adults. W e show how these strategies have.