1)
How did Hashem cut off Goyim?
1.
Rashi: I brought punishment on them, so you will see and fear - "Amarti Ach Tir'i Osi Tikchi Musar" (7).
2)
What do we learn from "Nashamu Pinosam"?
1.
Malbim: This was the first of three stages of cutting off nations. Pinosam are the sides and corners - the country's borders (they became desolate).
3)
Why does it add "Hecheravti Chutzosam"?
1.
Malbim: Chutzos are in back of the houses. The roads in the country were destroyed to the point that no one passes on them, for the enemy spread in the country.
4)
Why does it add "Nitzdu Areihem"?
1.
Malbim: Later, the cities themselves were destroyed to the point that there were no residents.