这块泥板刻有古老的苏美尔文字。

This clay tablet is inscribed with ancient ___Sumerian script.

苏美尔语是已知最古老的书面语言之一。

___Sumerian is one of the oldest known written languages.

苏美尔人建造了世界上最早的城市之一。

The ___Sumerians built one of the world's earliest cities.