Quote Originally Posted by Rodarian View Post
She was sorta being lil coy about it because while she knows what its meant for... Iflana *her bio Mom* must have told her earlier on what it was meant for....Of course Aerith didn't know how or rather when to use until the time came for her to do so...
I don't know if I'd say she didn't know how or when to use it. I'd say it's more likely she just knew it couldn't do anything yet because there was no big world ending threat like Meteor, or it might be that it wasn't meant to do anything until the Black Materia was used.

You're right though, looking at both translations it seems that she's just being coy, though it doesn't come across quite as well in the original translation.