[{'role': 'USR', 'utterance': 'Good afternoon, sir.'}
 {'role': 'SYS', 'utterance': 'Good afternoon. We want a table for 4.'}
 {'role': 'USR', 'utterance': "This way, please. It's near the window, so you'll have a good view. Sit down, please."}
 {'role': 'SYS', 'utterance': 'Thank you. Do you serve good Chinese food?'}
 {'role': 'USR', 'utterance': 'Yes, sir. We serve Chinese food of various styles, such as Hunan food, Sichuan food and Zhejiang food. The first two are a bit hot. Do you want to have a try?'}]
{'role': 'SYS', 'utterance': 'No, we like food that tastes a bit sweet.'}