This can be stated in active form. Alternate translation: "the dragon realized that God had thrown him out of heaven and sent him to earth" (See: [[rc://en/ta/man/translate/figs-activepassive]])
This was a large, fierce reptile, like a lizard. For Jewish people, it was a symbol of evil and chaos. The dragon is also identified in verse 9 as "the devil or Satan." See how you translated this in [Revelation 12:3](./03.md). (See: [[rc://en/ta/man/translate/writing-symlanguage]])