4. The method of claim 1 , further comprising: training the second machine translator, using the set of training data, to translate acceptable expressions for a value of the variable entity in the second natural language to corresponding canonical representations.
6. The method of claim 4 , further comprising: receiving an expression in the second natural language; using the second machine translator, translating at least a portion of the expression from the second natural language to a canonical representation of the at least a portion of the expression; and using a third machine translator, translating the canonical representation of the at least a portion of the expression into an equivalent expression in a third natural language.