郑和是中国历史上最著名的航海家。公元1405年，明朝政府为了稳固边防和开展海上贸易，派遣郑和下西洋。28年间，郑和带领船队七下西洋，前后出海的人员有10多万人，访问了30多个国家和地区。船队纵横南亚、西亚，一直到非洲大陆。郑和下西洋是世界航海史上的壮举，它展现了郑和卓越的航海和组织才能，同时展现了明朝的国力国威，加强了明朝和海外各国的联系。

答案：Zheng He was the most famous maritime explorer in Chinese history. In 1405, the government of the Ming Dynasty sent Zheng He on a voyage to the Western Seas in order to strengthen border defense and develop trade by sea. Within 28 years, Zheng He and his fleet made seven voyages to the Western Seas with over 100,000 crew members in total, and visited more than 30 countries and regions. The fleet travelled far into South Asia and West Asia, and made their way to the continent of Africa. Zheng He’s voyages to the Western Seas were a prodigious feat in the world navigation history. It demonstrated not only Zheng He’s outstanding navigational and organizational ability, but also the power and wealth of the Ming Dynasty. Meanwhile, it strengthened the relationships between the Ming Dynasty and the overseas countries.