1. A method comprising: receiving, by one or more processors of a data processing apparatus, a first string corresponding to an interpretation of a natural-language user voice entry, the natural-language user voice entry provided by a user via a microphone of a computing device of the user; providing, by one or more processors of the data processing apparatus, a representation of the first string as feedback to the natural-language user voice entry, the feedback for providing to the user via a graphical display or speaker of the computing device of the user; receiving, by one or more processors of the data processing apparatus and based on the feedback to the natural-language user voice entry, a second string corresponding to a natural-language corrective user entry, the natural-language corrective user entry provided by the user via the microphone of the computing device of the user and corresponding to a correction to the natural-language user voice entry; parsing, by one or more processors of the data processing apparatus, the second string into one or more tokens; determining, by one or more processors of the data processing apparatus, at least one corrective instruction from the one or more tokens of the second string, the at least one corrective instruction comprising an insert instruction; generating, by one or more processors of the data processing apparatus, from at least a portion of each of the first string and the second string and based on the at least one corrective instruction, a plurality of candidate corrected user entries, a token of the one or more tokens being inserted at a plurality of locations in the first string while maintaining all other tokens of the first string, based on the insert instruction, to generate the plurality of candidate corrected user entries; selecting, by one or more processors of the data processing apparatus, a corrected user entry from the plurality of candidate corrected user entries; and outputting, by one or more processors of the data processing apparatus, the selected corrected user entry for providing to the user via the graphical display or the speaker of the computing device of the user.