Produce a musical expression that follows the indicated alphabetical structure while integrating the provided thematic material.
X:1
L:1/8
M:4/4
K:G
['Bc BA GD GB dc Bc A2', 'G2 Bc BA GD GB dc Bc', 'G2 B2 d2 E2 FG AGFE D2']  
X:1
L:1/8
M:4/4
K:G
|: Bc BA GD GB | dc Bc A2 A2 | DEFG A2 AB | c2 BA B2 G2 |: Bc BA GD GB | dc Bc A2 A2 | DEFG A2 AB | 
 c2 BA G2 :: B2 d2 E2 FG | AGFE D2 D2 | DEFG A2 AB | c2 BA B2 G2 | B2 d2 E2 FG | AGFE D2 D2 | 
 DEFG A2 AB | c2 BA G2 :|  