azdskldfdfkdfff binch! Spoiler C - D - E - F - G - A - B Do = C Re = D Mi = E Fa = F Sol = G La = A Si = B As for the numbers, they represent how low or high the notes are (C5 is higher than C4, lower than C6). If you see a '#' or 'b' in between the letter and the number, it means sharp (#) or flat (b). So for example, on Valentine's Girl, Heejin hits a mixed D5 on 2:46, scales up really quickly on E5 but comes back down on D5. And we don't talk about the end of that belt xoxo. Thanks for coming to my ted talk! See you tomorrow for another lesson on vocals by Vivi Carey.