external orifice of male urethra

例句：

1. 1. The surgeon carefully removed the external orifice of the wound.
   外科医生小心翼翼地切除了伤口的外部开口。
2. 2.The engineer designed a new external orifice for the ventilation system.
   工程师设计了一个新的通风系统的外部开口。
3. 3.The scientist discovered an unusual external orifice on the underside of the planet.
   科学家在这颗行星的底部发现了一个不寻常的外部开口。