4 letter words:
feis7,
feus7,
foes7,
fous7,
fuse7,
seif7,
ufos7,
euoi4,
3 letter words:
efs6,
fes6,
feu6,
fie6,
foe6,
fou6,
ifs6,
sif6,
ufo6,
ios3,
iso3,
oes3,
ose3,
ous3,
sei3,
sou3,
sue3,
sui3,
use3,
2 letter words:
ef5,
fe5,
if5,
of5,
es2,
io2,
is2,
oe2,
oi2,
os2,
ou2,
si2,
so2,
us2,