Compose a musical piece in accordance with the outlined theme and structure.
X:1
L:1/8
M:4/4
K:D
['AF F2', 'fa a2'  
X:1
L:1/8
M:4/4
K:D
 B | AF F2 AFBF | AF F2 ABDF | AF F2 ABde | f2 af fed :| e | fa a2 fb b2 | fa a2 afde | 
 fa a2 fb b2 | afdf efde | fa a2 fb b2 | fa a2 afde | dBAF ABde | f2 af fed |]  