A．It is cheaper to travel by train than by plane.
B．The railway station is usually at the center of a city.
C．When you get off the plane you will find yourself right in the city center.
D．No motorcar or plane can carry as many goods as a train does,

A．随着石油工业的稳步发展，越来越多高质量的石油产品远销海外。
B．随着石油工业的迅速发展。越来越多高质量的石油产品被生产出来。
C．尽管石油工业发展缓慢，生产出的石油产品质量却越来越高。
D．由于石油工业的飞速发展，越来越多高质量的石油产品出口到国外。