First off, this is a big score and I spent like $2.00 trying to unsuccessfully copy this. Blast. Anyway, the Ravel is yet another example of complex ternary form. From the look of it, it looks really dang complex.
The A section appears to be a rounded closed binary form. In the a section we have a confused expository section. The first phrase appears to end on a PAC in G major, the second phrase seems to flirt with b minor, yets ends on a B major chord. Progressive period maybe? The next sixteen measures of the b section are developmental of the orinal theme. We see little two bar phrases ending on HC to make a large phrase group. We see a register change in the melody as the a section comes back, suggesting a somewhat rounded binary form ending on a PAC in the key of G major.
Here comes the B setion. Woot woot. It is much smoother and flowing compared to the prior section. The first 8 bars end in a d minor IAC, with the following 8 following suit. There are some crazy hand-crossing register-changing-stuff in the second half of the c section which leads us to the even more complex d section. I am probably wrong, But I would consider much of the d section a section in structure, as it primarily transitional. I love the HUGE chords in the middle of the piece. Cool. We hear a repeat of the c section material at the end of the B section, finishing this closed rounded binary form off on a d minor PAC.
Finally we come full circle to the A section. Although similar, the repeat of the original expository material is slightly different. Near the end we see a completely different accompanimental approach and colorful ornaments to slowly bring this beautiful piano piece to a close.