Will the land eulogize?
Radak: The people of the land will eulogize the one who was stabbed.
What do we learn from "Mishpachos Mishpachos"?
Radak: [Each will eulogize] in its place. The families mentioned, e.g. Nasan and Shim'i, will be big and known at the time. The Navi mentioned them in the way of Nevu'ah.
Malbim: Each family will make a eulogy by itself.
Why will the women be alone?
Rashi (14), Radak #1: This is for modesty.
Radak #2: Women lament and eulogize more than men do. They will be by themselves, to eulogize like their custom.
What is "Beis Nasan"?
Rashi #1: [The house of Nasan] ha'Navi.
Rashi #2: [The house of Nasan] ben David ? "Shamu'a v'Shovav v'Nasan u'Shlomo [were his sons]" (Shmuel II, 5:14). Malbim ? even though it is included in Beis David, it will be distinguished by itself.