1. A speech processing system comprising: a speech recognition unit configured to receive and perform speech recognition on input speech to produce a speech recognition result using acoustic models; and a natural-language processor configured to perform natural language processing on said speech recognition result, said natural-language processor including: a speech zone detector configured to detect correct zones from said speech recognition result; a feedback unit configured to feed back information obtained as a result of the natural language processing performed on said speech recognition result to said speech recognition unit, the feedback information including said detected correct zones, wherein said speech recognition unit includes an adaptation processor to process the feedback information from said feedback unit to adapt said acoustic models so that said speech recognition unit produces the speech recognition result with higher precision than when said adaptation processor is not used.