Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
M:4/4
K:C
['ecgc ec e/f/g/e/', "cc' AcEA AB B/c/d/B/ AcEc GcEc FcEc", 'gegc gegc', "c'2 ecBc (3GAB cG EC cE FDdF"]  
X:1
L:1/8
M:4/4
K:C
 f | ecgc ec e/f/g/e/ | fdad fd f/g/a/f/ | ecgc ec e/f/g/e/ | A/B/c/A/ B/c/d/B/ cc' :: 
 AcEA AB B/c/d/B/ | AcEc GcEc | FcEc Dc B/c/d/B/ | A/B/c/A/ B/c/d/B/ c2 a2 :: gegc gegc | 
 afad afad | gegc gegc | A/B/c/A/ B/c/d/B/ c2 c'2 :: ecBc (3GAB cG | EC cE FDdF | (3GAB c2 acgc | 
 A/B/c/A/ B/c/d/B/ c2 c'2 :|  