5. The system of claim 4 , wherein the at least one processor is to associate the sentence with a second probability, the second probability representing a likelihood that the sentence will translate into at least one expression of the database language query that produces the correct answer to the new natural language query.
4. A system comprising: at least one processor to: learn to translate natural language queries into database language queries using historical data associated with previously received natural language queries; respond to a new natural language query based on an analysis of the historical data, the historical data comprising: associations between keywords contained in the previously received natural language queries and attributes of a database model, the associations including associations between a first of the keywords and multiple attributes of the database model; and a context free grammar, the context free grammar being adaptable for disambiguating associations between an attribute of the database model and multiple attribute types, the multiple attribute types comprising a database table, a database column, and a value in a database table, the context free grammar further comprising a sentence including elements of a formerly received natural language query, and including a label replacing a given keyword in the formerly received natural language query and representing one of the database attribute types, the one database attribute type corresponding to the attribute of the database model associated with the given keyword; and associate a given association between a keyword in the new natural language query and a respective attribute of the database model with a first probability, the first probability representing a likelihood that the given association will translate into at least one expression of a database language query that produces a correct answer to the new natural language query.