This paper discusses different usage scenes for foreign service ports in Hainan Free Trade Port, and the translation strategy of the English speech under such a scene situation; It studies the language features of three main scenarios, sea law enforcement, ship agency, and marine search-and-rescue, and how context-based interpretation can play an important part in facilitating effective cross-language communication at sea: enhancing the professionalization of services, and guaranteeing safe operations. This paper finds some practical problems, such as the discrepancy between discussion and cases, lack of professional and common terms combination, lack of translation skills for translators. In line with international development requirements for free trade port shipping service, which suggests concrete actions in three areas: standardization, expression merging practice, and training professional skills. These findings can provide theoretical guidance and practical suggestions to improve the English language expression precision degree of foreign-oriented marine service, as well as to develop a special international marine service system.