For this verse see 8.13; 9.12. It seems that The second woe refers to the disasters that followed the blowing of the sixth trumpet (9.13-21); the events described in 10.1–11.13 come as an interval between the blowing of the sixth trumpet and the blowing of the seventh trumpet. Some believe that the second woe refers to the disaster described in 11.13. It is not easy to identify the third woe, which “is soon to come.” No disaster falls upon humanity after the blowing of the seventh trumpet. Many believe that the disasters and sufferings that come at the outpouring of the seven bowls of God’s anger (chapter 16) are the third woe; but the writer himself does not say so.

Quoted with permission from Bratcher, Robert G. and Hatton, Howard A. A Handbook on The Revelation to John. (UBS Handbook Series). New York: UBS, 1993. For this and other handbooks for translators see here .