Translation of "15th" in Chinese

During the 15th century, the Ryukyu Kingdom was a tributary state of Imperial China.

在15世紀，琉球王國是中國帝國的附庸國。

In the Ming Dynasty (early 15th century) the centre of Beijing was the Forbidden City.

明代十五世纪初紫禁城是北京的中心。

Before the 15th century it was generally believed that the Earth was at the centre of the universe.

在15世纪以前，人们曾经普遍认为地球位于宇宙的中心