7. The computer program product of claim 6 , wherein the program instructions to search the plurality of created tuples to identify one or more tuples that match the received topic further comprise: program instructions to identify a third tuple of the plurality of created tuples, the third tuple having a subject that matches the object of the first tuple; and program instructions to identify a fourth tuple of the plurality of created tuples, the fourth tuple having an object that matches the subject of the second tuple.
9. The computer program product of claim 7 , wherein the program instructions to generate a summary of the document comprising the sentences that correspond to the one or more identified tuples that match the topic comprise: program instructions to generate a summary comprising sentences corresponding to the first tuple, the second tuple, the third tuple, and the fourth tuple of the plurality of created tuples.