5. The method of claim 2 , wherein identifying candidate command sentences that include at least one first n-gram and a third n-gram that has not yet been determined to be a first n-gram or a second n-gram comprises identifying candidate command sentences that include at least one first n-gram and only one third n-gram.
5. The method of claim 2 , wherein identifying candidate command sentences that include at least one first n-gram and a third n-gram that has not yet been determined to be a first n-gram or a second n-gram comprises identifying candidate command sentences that include at least one first n-gram and only one third n-gram. 6. The method of claim 5 , wherein the third n-gram is a unigram.