Cooperative Model Based Language Understanding in Dialogue 
 In this paper, we propose a novel Cooperative Model for natural language understanding in a dialogue system . We build this based on both Finite State Model (FSM) and Statistical Learning Model (SLM) . FSM provides two strategies for language understanding and have a high accuracy but little robustness and flexibility. Statistical approach is much more robust but less accurate. Cooperative Model incorporates all the three strategies together and thus can suppress all the shortcomings of different strategies and has all the advantages of the three strategies. 