en_tn_condensed/rev/12/15.md

serpent

This is the same being as the dragon mentioned earlier in Revelation 12:9.

poured water out of his mouth like a river, that

The water flowed from his mouth like a river flows. Alternate translation: "poured a very large amount of water out of his mouth so that" (See: rc://en/ta/man/translate/figs-simile)

to sweep her away

"to wash her away"