1)
What is the meaning of "v"Nashamu b'Soch Aratzos Neshamos?
1.
Radak: The lands of Egypt will be desolate; they will be bi'Chlal (included in) the destroyed lands.
2.
Malbim: All the lands on that side of Migdol Sevenah will be desolate.
2)
Why does it add "v'Arav b'Soch Arim Nacharavos?
1.
Radak: The matter is repeated in different words.
2.
Malbim: Refer to 29:12:2:1.