The current primitive materials about Zheng's voyage were not complete, but we are not short of historical materials. The basic facts of Zheng's navigation are clear.
现存关于郑和航海的原始资料虽然不是很完整，但有关的史料还是不少，郑和航海的基本史实是清楚的。
2
The places Zheng passed by were where monsoon was very prominent, and the seasonal changes of prevalent wind would lend to seasonal changes of ocean current, thus greatly facilitating Zheng's voyage.