1. A method of machine-interpreting freeform text, the method comprising, by a computer system: receiving input data over a computer network; automatically generating topic-based metadata of the input data in relation to a multi-level taxonomy; automatically determining parts of speech of tokens of the input data; searching a metadata store using the tokens and the parts of speech, the searching comprising identifying, at a first level and a second level of the multi-level taxonomy, nodes that include metadata which sufficiently match the tokens and the parts of speech of the tokens, wherein the searching yields best-match grammar-based metadata; and revising the best-match grammar-based metadata based at least in part on the automatically generated topic-based metadata.