12. The system of claim 11 , wherein the processing module is further operable to build a parse tree of the natural language expression, the processing module identifying the words using the parse tree.
12. The system of claim 11 , wherein the processing module is further operable to build a parse tree of the natural language expression, the processing module identifying the words using the parse tree. 14. The system of claim 12 , wherein the processing module is further operable to store unrecognized words in the parse tree as comments.