10. The non-transitory computer-readable storage medium of claim 8 , wherein allowing the compact mathematical expression to be altered comprises instructions for receiving inputs from at least one of: adding a word to the mathematical expression, deleting a word from the mathematical expression, making a common word in the mathematical expression optional; and making an optional word in the mathematical expression common.
8. The non-transitory computer-readable storage medium of claim 7 comprising instructions for allowing the compact mathematical expression to be altered.