10 letter words:
unfruitful16,
8 letter words:
fruitful14,
6 letter words:
fitful12,
tinful9,
unfurl9,
5 letter words:
flint8,
flirt8,
fruit8,
unfit8,
rutin5,
unlit5,
until5,
4 letter words:
luff10,
riff10,
ruff10,
tiff10,
tuff10,
firn7,
flir7,
flit7,
frit7,
furl7,
lift7,
rift7,
turf7,
lint4,
litu4,
lunt4,
nurl4,
ruin4,
runt4,
tirl4,
turn4,
unit4,
3 letter words:
iff9,
fil6,
fin6,
fir6,
fit6,
flu6,
fun6,
fur6,
rif6,
lin3,
lit3,
nil3,
nit3,
nut3,
rin3,
run3,
rut3,
til3,
tin3,
tui3,
tun3,
ulu3,
urn3,
2 letter words:
if5,
in2,
it2,
li2,
nu2,
ti2,
un2,
ut2,