Craft a musical piece that abides by the prescribed structural guidelines and the given theme.
X:1
L:1/8
M:2/4
K:C
['A B', 'B c4', 'e e g e', 'd d4- d2'  
X:1
L:1/8
M:2/4
K:C
 A B ||[M:3/4] c2 d2 c B ||[M:2/4] A G A B |[M:3/4] c2 d2 A B | c4 c3/2 d/ || 
[M:4/4] e e g e d (3d c d | e2 c4 c3/2 d/ | e e g e d2 (3d c d | d4- d2 z2 |]  