1)
What are "Aravim"?
1.
Rashi: They are willow trees by the river.
2)
Why did they suspend their harps?
1.
Radak: First they were in their hands. When they recalled Tziyon, they cast them off, and hung them on the willows.
2.
Malbim: We did not want to rejoice in the good of Bavel. We mourned that the enemy's land is full of willows and pleasure, and Hashem's city is desolate.
