en_tn/rev/20/01.md

General Information:

John begins to describe a vision of an angel throwing the devil into the bottomless pit.

Then I saw

Here "I" refers to John.

bottomless pit

This is an extremely deep narrow hole. Possible meanings are 1) the pit has no bottom; it continues to go down further forever or 2) the pit is so deep that it is as if it had no bottom. See how you translated this in Revelation 9:1.