Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
M:2/4
K:D
['f>edB d e3 e>BAd B/A/F']  
X:1
L:1/8
M:2/4
K:D
 f>edB | d e3 | e>BAd | B/A/F E2 | f>edB | d e3 | e>BAd | B/A/F A2 |]  