Marks in the text that indicate where the singer breathes. Proper breath phrasing is the foundation of singing technique.
Mark breathing spots (usually at phrase ends). Don't breathe mid-word. Plan breaths so they don't interrupt the thought.
Breath is the fuel of the voice. Bad breathing = unstable tone, loss of control. Good breathing = relaxed, full tone.
Exercise: inhale 4 counts, hold 4, exhale 8. Gradually extend the exhale.