Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/8
M:2/2
K:D
['dA A2 (AF)AB dA f2 ef dB', 'd2 (ef)ge']  
X:1
L:1/8
M:2/2
K:D
 fe"A" |]"D" dA A2 (AF)AB |"D" dA A2{a}"D7" f2 ef |"G" dB B2({d} BA)Bd |"Em" ABd(e"A7" fa)ef | 
"D" dA A2 (AF)AB |"D" dA A2"D7"{a} f2 ef |"G" dB B2({d} BA)Bd |"Em" ABd(e{a}"A7" f2) |] ef | 
"D" d2 fd"Em" (ef)ge |"D" d2 fd"A7" e2 cA |"D" d2 fd"G" (ef)ge |"Em" aA A2"A7"{a} f2 ef | 
"D" d2 fd"Em" (ef)ge |"D" defd"A7" e2 (cA) |"D" defd"G" efg(e |"Em" ab)a(g"A7" af)ef |]  