billboard poster宣传招贴或海报 underpin v.巩固,加强的基础 tsunami n.海啸 skeptical adj.怀疑的 hurricane n.飓风 pay off得到回报 volatile adj.不稳定的;可变的 电梯elevators and escalator 持续扩张 continuously expand 自动扶梯 moving walk 个性化的 highly individual 旅客登机桥 passenger boarding bridge 全...