[{'role': 'USR', 'utterance': 'Do you think we should travel by bus or by train?'}
 {'role': 'SYS', 'utterance': "It's a difficult choice.The train is a little faster, but much more expensive."}
 {'role': 'USR', 'utterance': 'We could face delays if we travel by bus, thanks to traffic jams.'}
 {'role': 'SYS', 'utterance': "Buses are more cramps and you can't walk around."}
 {'role': 'USR', 'utterance': "That's true.But I feel that I see more when I travel by bus."}
 {'role': 'SYS', 'utterance': 'Really? I think you see more traveling by train.'}
 {'role': 'USR', 'utterance': 'So which form of transport do you prefer to use?'}]
{'role': 'SYS', 'utterance': 'I prefer going by train, even though it costs more.'}