Develop a musical piece that combines the given theme and letter-structured outline.
X:1
L:1/8
M:6/8
K:D
['Add Bdd', 'd3 d2 a agf ged cBA dfa']  
X:1
L:1/8
M:6/8
K:D
 Add Bdd | Add Bdd | ABc def | gee e3 | Add Bdd | Add Bdd | ABc def | edc d3 || d2 a agf | 
 ged cBA | dfa agf | gab a2 f | gbg faf | efd cBA | ABc def | edc d3 |]  