6. A computer-implemented method for facilitating multimodal interaction, the method comprising: receiving a spoken utterance having two or more terms, the two or more terms including one or more acceptable terms; searching an index using the one or more acceptable terms as query terms; producing using a computer processor, from the searching of the index, at least one permissible phrase that includes the one or more acceptable terms; the index comprising a searchable data structure that represents multiple possible grammar paths that are ascertainable based on acceptable values for each term position of a grammar-based speech application; and presenting the at least one permissible phrase to a user as at least one option that may be selected to conduct multimodal interaction with the device.
6. A computer-implemented method for facilitating multimodal interaction, the method comprising: receiving a spoken utterance having two or more terms, the two or more terms including one or more acceptable terms; searching an index using the one or more acceptable terms as query terms; producing using a computer processor, from the searching of the index, at least one permissible phrase that includes the one or more acceptable terms; the index comprising a searchable data structure that represents multiple possible grammar paths that are ascertainable based on acceptable values for each term position of a grammar-based speech application; and presenting the at least one permissible phrase to a user as at least one option that may be selected to conduct multimodal interaction with the device. 13. The method as recited in claim 6 , wherein producing comprises: retrieving from the index one or more retrieved acceptable terms as part of the at least one permissible phrase; wherein the method further comprises: for a forward case in which the one or more acceptable terms from the spoken utterance comprise one or more recognized acceptable terms that initiate the at least one permissible phrase, presenting the one or more recognized acceptable terms followed by the one or more retrieved acceptable terms.