Explanation:

Rivers forming the borders of Mesopotamia:

Mesopotamia is a historical region located in Western Asia, primarily within the Tigris-Euphrates river system. The two rivers that form the borders of Mesopotamia are the Tigris and Euphrates.

Tigris River:
The Tigris River is one of the two main rivers of Mesopotamia. It originates in the Taurus Mountains of eastern Turkey and flows through Iraq before joining the Euphrates River. The Tigris River has played a significant role in the history and development of Mesopotamia, providing water for agriculture and transportation.

Euphrates River:
The Euphrates River is the other main river that forms the borders of Mesopotamia. It also originates in eastern Turkey and flows through Syria and Iraq before joining the Tigris River. Like the Tigris, the Euphrates River has been crucial for the civilizations that developed in Mesopotamia, providing fertile land for agriculture and serving as a transportation route.

Significance of the Tigris and Euphrates Rivers:
The Tigris and Euphrates Rivers were vital to the development of ancient Mesopotamian civilizations such as Sumer, Akkad, Babylon, and Assyria. The fertile land along the riverbanks supported agriculture, leading to the growth of urban centers and the emergence of complex societies. The rivers also facilitated trade and communication, allowing for the exchange of goods and ideas between different regions.

In conclusion, the Tigris and Euphrates Rivers are the two main rivers that form the borders of Mesopotamia, playing a crucial role in the history and development of this ancient region.