4 letter words:
bard7,
baud7,
brad7,
burd7,
darb7,
daub7,
drab7,
drub7,
abut6,
brat6,
brut6,
bura6,
tabu6,
tuba6,
dart5,
daut5,
drat5,
dura5,
trad5,
turd5,
3 letter words:
bad6,
bud6,
dab6,
dub6,
arb5,
bar5,
bat5,
bra5,
bur5,
but5,
rub5,
tab5,
tub5,
urb5,
rad4,
tad4,
urd4,
art3,
rat3,
rut3,
tar3,
tau3,
uta3,
2 letter words:
ab4,
ba4,
ad3,
ar2,
at2,
ta2,
ut2,