Craft a musical piece that abides by the prescribed structural guidelines and the given theme.
X:1
L:1/8
Q:1/8=180
M:4/4
K:D
['d2 Ad fdAF', 'gbag fagf gfeg'  
X:1
L:1/8
Q:1/8=180
M:4/4
K:D
 A | d2 Ad fdAF | GFEF GABc | d2 Ad fdAF | GBAG FD D2 | d2 Ad fdAF | GFEF GABc | d2 Ad fdAF | 
 GBAG FD D2 || fagf gbag | fagf gfeg | fagf gbag | fgeg fddA | dfaf gbag | fagf gfeg | fedc dcBA | 
 GABc dgfe ||  