1. A method comprising: creating a rule-based grammar having a wildcard identifier in place of a predefined category of words; defining rules to produce artificial combinations of unique sounds in a language, where each artificial combination represents a pronunciation of the words in the predefined category, and represents a generic word that is defined in a speech engine's vocabulary database; generating a set of artificial combinations of unique sounds by substituting the wildcard identifier with the rules; and in response to human speech specifying a wildcard word, determining a number of potential words spoken by the user by finding the generic words and non-generic words that phonetically match the wildcard word, and then assigning each of the words a confidence level.