Complex sentence: The Sumerians didn't had oldest writing the Indus valley had it is a undeciphered script older than Sumerian cuneiform the writings are mystery it had science technology that could change the world the Indus valley is the back bone of Mesopotamian and Egyptian civilizations.
Split into simpler sentences: The Sumerians didn't had oldest writing the Indus valley had. It is a undeciphered script older than Sumerian cuneiform the writings are mystery it had science and technology that could change the world the Indus valley is the back bone of Mesopotamian and Egyptian civilizations.