1)
What will your children do quickly?
1.
Rashi: Lashuv (Malbim - repent 1 ). Radak - past tense is used in place of future; this is common in Nevu'ah.
1
I am unsure if Rashi agrees, or if he means that they will return to Eretz Yisrael. (PF)
2)
What is the meaning of "Meharsayich u'Macharivayich Mimech Yetze'u"?
1.
Radak: Your sinners will be eradicated; there will not be evil in you, They were the cause of the destruction!
2.
Malbim: Your enemies who destroyed you, they would have left you many days ago had your children wanted, and quickly repented from their sins.