短语词组短语drop -arm barrier 起落栏栅drop shaft arm 翻译maximum drop to arm 引信解除保险最大落下距离drop arm barrier 垂臂式栏栅Drop arm test 试验;测试;垂臂检查;落臂征steering drop arm 转向臂;转向垂臂Buy Drop Arm 转向垂臂arm drop sign 肩坠落试验Sky Arm Drop 天空胳膊落 返回 drop arm