With so many people using Tokyo’s trains and metro lines during rush hour, station staff sometimes need to help every passenger board the train. These workers are called oshiya or “pushers.” As the name suggests, oshiya are there to push passengers from the platform into the train so that the train can depart on time. Oshiya are seen only during rush hour and at a few large stations in the city. They were first introduced at Shinjuku Station as passenger arrangement staff.
board vt. 登上（火車、飛機等）
on board 在火車∕飛機等大型交通工具上（可作副詞或介詞）
platform n. 月臺
on time 準時