# Yahweh said to Moses, "Reach out with your hand ... and their horsemen."

This can be stated as an indirect quote. AT: "Yahweh told Moses to reach out with his hand over the sea so that the waters would come back onto the Egyptians, their chariots, and their horsemen."

# come back onto

"fall on"

# The Egyptians fled into the sea

Since the sea was closing in on top of the Egyptians, instead of escaping, they were actually running right into the water.

# Yahweh drove the Egyptians

"Yahweh pushed the Egyptians" or "Yahweh threw the Egyptians"