[{'role': 'USR', 'utterance': "Excuse me, sir. You can't park here."}
 {'role': 'SYS', 'utterance': "I am just waiting for my friends. It won't be long."}
 {'role': 'USR', 'utterance': 'Sir, the curb here is not for parking.'}
 {'role': 'SYS', 'utterance': "But I didn't see the sign, Ma ' am."}
 {'role': 'USR', 'utterance': 'There is a sign at the corner of the street. When you turned in here, you should have seen it.'}]
{'role': 'SYS', 'utterance': "I didn't see it."}