Revelation 8:13 V-PNA
BIB: τῶν μελλόντων σαλπίζειν
NAS: angels who are about to sound!
KJV: which are yet to sound!
INT: who [are] about to sound [their] trumpets

Revelation 10:7 V-PNA
BIB: ὅταν μέλλῃ σαλπίζειν καὶ ἐτελέσθη
NAS: he is about to sound, then
KJV: he shall begin to sound,
INT: when he is about to sound [the] trumpet also should be completed