1. A method comprising: receiving a single input communication from a user in a spoken dialog system; generating, via a processor and in response to the single input communication, a plurality of communication goals, wherein the plurality of communication goals are based on a dialog strategy; generating a plurality of sentence plans corresponding to the plurality of communication goals, wherein each sentence plan of the plurality of sentence plans comprises elementary speech acts and is a viable and potentially usable prompt in response to the single input communication; and presenting to the user a selected sentence plan from the plurality of sentence plans as a response to the single input communication.