1. An information retrieval system, comprising: a knowledge model database configured to store a knowledge model for a knowledge domain, the knowledge model defining a plurality of entities and interrelationships between one or more of the plurality of entities, the plurality of entities including concepts and instances; a knowledge base identifying a plurality of items, each of the plurality of items being associated with at least one annotation identifying at one of the entities in the knowledge model; a template repository storing a plurality of templates, each of the plurality of templates including a concept and a relationship from the knowledge model; and a query processing server configured to: retrieve one of the templates from the template repository, transmit the template to a client computer, receive, from the client computer, a statement, the statement including an instantiation of the template, and query the knowledge base using the statement to generate a result listing identifying an item in the knowledge base.