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:Bb
['(c>d) (B>c)(B>G) (.F2 .B2 .B2) (d>e)', '(f>g) (_a>g)(a>b) .a2']  
X:1
L:1/8
M:4/4
K:Bb
 (f>e) | .d2 (c>d) (B>c)(B>G) | (.F2 .B2 .B2) (d>e) | (.f2 .b2 .f2) (f>e) | (d>e)(c>d) .B2 (f>e | 
 .d2) (c>d) (B>c)(B>G) | (.F2 .B2 .B2) (d>e) | .f2 (b>g) (f>e)(d>c) | B4- B2 :: (f>g) | 
 (_a>g)(a>b) .a2 (f>g) | (_a>g)(a>b) .a2 (c>d) | (e>d)(e.f) (e>d)(e>f) | (e>d)(e>f){ef} g2 (f>e) | 
 .d2 (c>d) (B>c)(B>G) | (.F2 .B2 .B2) (d>e) | .f2 (b>g) (f>e)(d>c) | (B4 B2) :|  