I'm studying with a book called "Analyzing Classical Form" and it says that the cadence in this piece starts it's cadence on the 2nd half of m 10 but that's a III(5) and I'm so confused.
If I analyzed it correctly it goes like this:
m10.5: III(5)
m11: IV (Csus#4 but I think it can be described as the IV)
m11.5: II
m12: I(64)
m12.375: I(764)
m12.5: V(7) Repeated for 3 times (eights)
m12.875: vii°(9)
m13: I
Can anyone explain to me why the cadence starts on m10.5?
Why does this Cadence start on a III? I've heard people calling it everything from Tonic to substitute Dominant so I'm confused.
Why does it go D-Pd-T-D-D-T (Pd = pre-dominant)
If the normal structure is T-PD-D-T for a perfect authentic cadence does that mean that I could insert (in common time and 1 chord per bar) 2 Dominants with half a bar of length for the D?
PS. At this point even my confusion is confused so don't be sacred to write a long answer, it'd help me a lot. Just explaining from ground up why for God's sake this is a complete cadence (I get that eveything is in there but the order and the amount of chords is what confuses me)