fathomn.英寻（=6英尺)vi.测量深度vt.彻底了解；测深fathom a mystery探测奥秘fathomless motives无法理解的动机fathometer sounding测深仪测深fathometer transducer回声测深仪变换器fathom with a plumb line用铅垂线测深Fathom Five National Marine Park以及去以潜水活动闻名的五尺深国家海洋公园