Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/8
M:4/4
K:G
['DF G2 DG', 'd2 efge']  
X:1
L:1/8
M:4/4
K:G
 DF |:"G" G2 DG B2 GB | dBeB dBAB |"G" d2 Bd"C" efge |"D" dBAB"Em" GEDE |"G" G2 DG B2 GB | 
 dBeB dBAB |"G" d2 Bd"C" efge |1"D" dBAB"G" G2 DF :|2"D" dBAB"G" G2 Bc ||"G" dggf g2 dg | 
 g2 bg aged |"Am" eaag a2 eg |"D" a2 bg ageg |"G" dggf g2 dg | g2 bg aged |"G" d2 Bd"C" efge |1 
"D" dBcA"G" G2 Bc :|2"D" dBcA"G" G2 ||  