1)
Why does it say "Ki"?
1.
Rashi: Do not say, why should I write it? All will perish, and no one will read them! Do not say so - I will return the exile...
2.
Malbim: Write it, so in the future, the last generation will know.
2)
Which redemption does this discuss?
1.
Radak: It is the final redemption, when Yisrael and Yehudah will return. Only Yehudah and Binyamin returned from Bavel.
3)
Why does it say both "v'Shavti" and "va'Hashivosim"?
1.
Malbim: I will return them to their level, and return them to their land.