4 letter words:
babu8,
barb8,
buba8,
burb8,
brag7,
burg7,
garb7,
grab7,
grub7,
baur6,
bura6,
gaur5,
guar5,
ruga5,
3 letter words:
abb7,
bub7,
bag6,
bug6,
gab6,
gub6,
arb5,
bar5,
bra5,
bru5,
bur5,
rub5,
urb5,
gar4,
gau4,
gur4,
rag4,
rug4,
2 letter words:
ab4,
ba4,
ag3,
gu3,
ug3,
ar2,
ur2,