assistor
n. 帮助者;加力器;助推器
例句
The invention relates to a bike with an assistor, in particular to a bicycle, tricycle or tetra-cycle with an assistor, comprising a frame, a rear axle, a front axle and a middle shaft.
本发明涉及一种具有助力装置的脚踏车,尤其是指具有助力 装置的自行车、三轮脚踏车或四轮脚踏车。