短語(yǔ)詞組短語(yǔ)beach boom -line 泳灘浮波界線boom line relief valve 動(dòng)臂油路安全閥swimming boom line area 浮泡界線範(fàn)圍Catline Boom and Hoist Line 懸臂吊繩纜straight line apron boom 直線跳板式攔河埂 返回 boom line