en_tn/deu/29/24.md

they will say together with all the other nations ... mean?

This can be translated as an indirect quotation. AT: "they will ask with all the other nations why Yahweh has done this to the land, and what the heat of this great anger means." (See: rc://en/ta/man/translate/figs-quotations)

they will say together with all the other nations

"your descendants and the people of all the other nations will say"

What does the heat of this great anger mean?

The writer is communicating one idea through two words. AT: "What does this terrible anger mean?" (See: rc://en/ta/man/translate/figs-hendiadys)