这部书主要讲的是冷战时期的苏美关系。

The book is primarily concerned with Soviet-American relations during the Cold War.

《牛津词典》

苏美尔文明就是在这里出现的，其最早的形式诞生于公元5世纪。

It was here that the civilization known as Sumer emerged in its earliest form in the fifth millennium.

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这样的探险可以追溯到古苏美尔时期，这是已知的最早的中东文明。

One can trace such expeditions back to ancient Sumeria, the earliest known Middle Eastern civilization.

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