短語詞組短語south navigation channel 南航道siltation in navigation channel 航道回淤estuary navigation channel regulation 河口航道整治navigation channel dredging 航道疏浚outer navigation channel 外航道mountainous navigation channel regulation 山區(qū)航道整治signal for navigation channel 通航水道信號(hào)deep navigation channel 深水航道工程navigation channel variation 航道變化 返回 navigation channel