你准备去一个城市,当你走进汽车站,来到售票处时,售票员告诉你,通往那个城市的公路因被大雪封阻而无法通车。这样,你就无法去那个城市了吗?当然不是,你可以改乘火车。当你来到火车站售票处时,售票员告诉你,通往那个城市的铁 You are ready to go to a city. When you come to the bus station and come to the ticket office, the conductor tells you that the road leading to that city can not be opened due to heavy snowfall. In this way, you can not go to that city? Of course not, you can change to the train. When you come to the train station ticket office, the conductor told you that the iron leading to that city