A passenger or cargo system of public or private transportation, as by ship, aircraft, or bus, usually over a definite route. (固定路线的)运输系统通常有固定路线的公有或私有贷运或客运系统,如船运、空运或汽运
He'll go to America by ship tomorrow. 他明天要乘船去美国。
How long will it take to go there by ship? 乘船到那里去要花多长时间?
One can travel there by ship or plane. Most people choose the latter. 乘船或乘飞机都可以到那,人们多选择后者。