KJV:
And if the family of Egypt go not up, and come not, that have no rain; there shall be the plague, wherewith the LORD will smite the heathen that come not up to keep the feast of tabernacles.
NASB:
If the family of Egypt does not go up or enter, then no rain will fall on them; it will be the plague with which the LORD smites the nations who do not go up to celebrate the Feast of Booths.