水闸值班人

例句：

1. 1. The watergate duty officerwas responsible for monitoring the security of thegovernment buildings.
   水闸值班员负责监督政府大楼的安全。
2. 2. The gatekeeper at theentrance had to ensure that only authorized individualswere allowed in.
   入口处的门卫必须确保只有授权人员可以进入。
3. 3. Theguardians patrolled thearea around the palace to preventany unauthorized access.
   守卫在宫殿周围巡逻，以防止未经授权的进入。