8. A method for matching a search query to text within a one or more documents comprising: receiving a natural language search query containing a plurality of words; assigning a primary grammatical role to a word in the search query; assigning an additional grammatical role to the word from the search query using a role hierarchy that defines a grammatical relationship between the primary grammatical role and the additional grammatical role, wherein grammatical roles within the role hierarchy get more specific the further grammatical roles are from a root grammatical role, and wherein the additional grammatical role fits within a definition of the primary grammatical role and has a more specific definition, wherein the additional grammatical role is a subservient grammatical role to the primary grammatical role, which is a dominant grammatical role; and determining, at a computing device, that at least one document referenced in an index, which associates the word and a sentence within the at least one document with one or more grammatical roles, includes the word from the search query assigned to one or more of the primary grammatical role and the additional grammatical role.
8. A method for matching a search query to text within a one or more documents comprising: receiving a natural language search query containing a plurality of words; assigning a primary grammatical role to a word in the search query; assigning an additional grammatical role to the word from the search query using a role hierarchy that defines a grammatical relationship between the primary grammatical role and the additional grammatical role, wherein grammatical roles within the role hierarchy get more specific the further grammatical roles are from a root grammatical role, and wherein the additional grammatical role fits within a definition of the primary grammatical role and has a more specific definition, wherein the additional grammatical role is a subservient grammatical role to the primary grammatical role, which is a dominant grammatical role; and determining, at a computing device, that at least one document referenced in an index, which associates the word and a sentence within the at least one document with one or more grammatical roles, includes the word from the search query assigned to one or more of the primary grammatical role and the additional grammatical role. 10. The method of claim 8 , further comprising generating additional words to search the index by adding at least one of a synonym and a hypernym for one or more words in the search query to a list of search terms, wherein a search term includes a single word and an associated role, and wherein the synonym and the hypernym form search terms with the roles assigned to the one or more words for which the synonym and the hypernym are synonyms and hypernyms.