[ It's not the first time she's had to teach from the very beginning. Well, maybe the first time she had to teach someone who's never been a human before... ]

Well, you're air comes out of your lungs. What you're doing with your diaphragm is trying to control your breathing, to keep the notes steady and powerful. So when someone says your sounds comes from your diaphragm, we just mean the depth of the note that you sing is controlled by your breathing. Like this:

[ Maki shifts her stance a little, and takes a deep breath for example, touching her hand to her stomach. And then she sings. ]

Do Re Mi~