5 letter words:
freer8,
frere8,
frore8,
refer8,
error5,
4 letter words:
fere7,
fern7,
fore7,
free7,
froe7,
reef7,
erne4,
3 letter words:
fee6,
fen6,
fer6,
foe6,
fon6,
for6,
fro6,
ref6,
eon3,
ere3,
ern3,
err3,
nee3,
nor3,
one3,
ore3,
ree3,
roe3,
2 letter words:
ef5,
fe5,
of5,
en2,
er2,
ne2,
no2,
oe2,
on2,
or2,
re2,