Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for generating rewrites are disclosed. In one embodiment, an original rewrite operation is identified with a source term and a target term, and queries containing the source term are identified. For each query, an importance score is identified for the source term, and for an additional term prior to or after the source term. If the importance weight of the additional term is greater than the source term, the additional term may be added to a new rewrite source. If the number of times the new rewrite source appears in the queries meets a threshold, a new rewrite operation may be generated which specifies the source term should be replaced with the target term, and including the additional term.