6 letter words:
unfree9,
5 letter words:
enure5,
4 letter words:
beef9,
feeb9,
enuf7,
fere7,
fern7,
free7,
reef7,
been6,
beer6,
bene6,
bree6,
bren6,
burn6,
rube6,
unbe6,
erne4,
rune4,
3 letter words:
fub8,
fee6,
fen6,
fer6,
feu6,
fun6,
fur6,
ref6,
bee5,
ben5,
bun5,
bur5,
neb5,
nub5,
reb5,
rub5,
urb5,
ere3,
ern3,
nee3,
ree3,
rue3,
run3,
urn3,
2 letter words:
ef5,
fe5,
be4,
en2,
er2,
ne2,
nu2,
re2,
un2,