Genesis 1:6

And God said, 'Let there be an expanse between the waters to separate water from water.'

(New International Version)

Then God said, 'Let there be an expanse in the midst of the waters, and let it separate the waters from the waters.'

(New American Standard Bible)

And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters.

(King James Version)