# The River will sweep onward into Judah, flooding and passing on, until it reaches to your neck
"More and more soldiers will come like a river rising up to your neck"
# Its outstretched wings will fill
Possible meanings are 1) as "the River" rises, its "wings" flow over and cover what had been dry land or 2) Isaiah then speaks of Yahweh as a bird who is protecting the land, "But his outstretched wings will cover."
# Immanuel
Translators may add a footnote that says: "The name Immanuel means 'God with us.'"