1)
Why are there two expression, "Kerovim Hem Elav" and "uv'Kirbo Hem Yoshvim"?
1.
Malbim: They are unlike the Girgashi, who were initially close and went to Africa. Since they were close, it was forbidden to make a Bris with them. Since they [continued] to live among them, they needed to accept taxes and servitude.
