1. A computer-implemented method for interacting with a user in a spoken dialog system, the method comprising performing at least one of the following steps via a processor: in response to information from a user's single input communication in a spoken dialog system, generating a plurality of sentence plans each sentence plan in the plurality of sentence plans being a realization comprising elementary speech acts each corresponding to a respective communicative goal and combined into at least one complete sentence that accomplishes a plurality of communicative goals and wherein each sentence plan of the plurality of sentence plans is a viable and potentially usable prompt in response to the user's single input communication; ranking the plurality of generated sentence plans; and presenting to the user a selected sentence plan from the plurality of sentence plans as a response to the user's single input communication.