Resurrection, the first
'The first resurrection,' mentioned in Revelation 20:5, 6, does not mean a first resurrection, but the essence and primary part of resurrection, which is salvation and eternal life. There is only one resurrection to life. A second does not happen, and is not mentioned anywhere in the Bible.
(References: Apocalypse Explained 6; Apocalypse Revealed 851; Revelation 20:5-6)
Three and a half
In Revelation 11:9, this signifies to the end and the beginning, or to the end of the present church and the beginning of a new church. (Apocalypse Revealed 505) It also signifies the same as a week because it is half of seven. (Apocalypse Revealed 505[2])