重点讲解：
1. the volume of
量；数额；
eg. The volume of passenger travel on the railways is increasing again.
铁路的客运量又在日益增加。
eg. We needed to increase the volume of production.
我们需要提高产量。
2. run down
（车辆）把…撞伤，撞倒；
eg. Lozano claimed that motorcycle driver Clement Lloyd was trying to run him down.
洛扎诺声称克莱门特·劳埃德骑着摩托车想把他撞伤。
eg. The old man was run down by a big lorry.
那个老人被一辆大卡车撞倒了。
3. on earth
（用于以how， why， what 或 where 开始的问句，表示强调，通常表示问题没有答案或很难回答）究竟，到底；
eg. How on earth did you know it?
你到底是怎么知道的？
eg. Why on earth didn't you tell me the truth?
你到底为什么不跟我说实话？