user_turns: <SILENCE> im looking for an expensive restaurant that serves vietnamese food how about in any price range vietnamese food in any price range <SILENCE> uh address the address thank you good bye
system_turns: Hello , welcome to the Cambridge restaurant system . You can ask for restaurants by area , price range or food type . How may I help you ? I'm sorry but there is no restaurant serving expensive vietnamese food Could you please repeat that? api_call vietnamese R_location R_price thanh_binh serves vietnamese food Can I help you with anything else? Sure , thanh_binh is on thanh_binh_address  you are welcome