user_turns: <SILENCE> i want a restaurant in the north part of town that serves vietnamese food what about in the west area <SILENCE> phone number whats the phone number 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 vietnamese restaurant in the north of town api_call vietnamese west R_price thanh_binh serves vietnamese food thanh_binh is a great restaurant The phone number of thanh_binh is thanh_binh_phone  you are welcome