... Events, and Relations An important property of a natural language system is that it often has only partial information about the individuals (objects, events, and relations) that are talked about. ... binary relations, we can generalize our representation by introducing the predicate ROLE and making rolenames into individuals in the domain. ROLE(o, r, v) asserts that individual o has ... define a predicate, DURING (a, b), that is true only if interval a is wholly contained in interval b. Now, if we want the retriever to automatically infer that if relation R holds during an interval...