短语词组短语backstop tone 后定位夹钳hydraulic backstop 以液压升降的篮球架backstop plan 保障安排liquidity backstop 防止流动性枯竭backstop inside 内支撑块backstop tongs 止退钳;后挡钳gearbox backstop 变速箱止回器relay backstop 继电器止档backstop welding 分段退焊 返回 backstop