1. A computer-implemented method for use with a document tangibly stored in a first computer-readable medium, the method comprising: (A) accessing the first computer-readable medium to identify a first phrase within the document, the first phrase representing a first written form of a concept; (B) identifying a two-way mapping between the first phrase and a second phrase tangibly stored in a second computer-readable medium, the second phrase representing a second written form of the concept; (C) replacing the first phrase with the second phrase in the document on the first computer-readable medium; (D) after (C), replacing the second phrase with the first phrase in the document on the first computer-readable medium; (E) before (C), receiving an instruction from a user to modify the first phrase; wherein (C) is performed in response to receipt of the instruction; and wherein the instruction does not include the second phrase.