1. A method for reducing response time in a speech interface comprising: constructing a partially completed word sequence from a partially received utterance from a speaker received by an audio sensor; modeling a remainder portion for the partially received utterance using a processor based on a rich predictive model to predict the remainder portion; and responding to the partially completed word sequence and the predicted remainder portion for the partially received utterance using a natural language vocalization generator with a vocalization, wherein the vocalization is prepared before a complete utterance is received from the speaker and conveyed to the speaker by an audio transducer.