6 letter words:
ferine9,
refine9,
entire6,
retine6,
triene6,
5 letter words:
feint8,
finer8,
infer8,
refit8,
enter5,
inert5,
inter5,
niter5,
nitre5,
rente5,
retie5,
terne5,
treen5,
trine5,
4 letter words:
feet7,
fere7,
fern7,
fete7,
fine7,
fire7,
firn7,
free7,
fret7,
frit7,
neif7,
reef7,
reft7,
reif7,
rife7,
rift7,
tref7,
erne4,
nite4,
rein4,
rent4,
rete4,
rite4,
teen4,
tern4,
tier4,
tine4,
tire4,
tree4,
3 letter words:
eft6,
fee6,
fen6,
fer6,
fet6,
fie6,
fin6,
fir6,
fit6,
ref6,
rif6,
ere3,
ern3,
ire3,
nee3,
net3,
nit3,
ree3,
rei3,
ret3,
rin3,
tee3,
ten3,
tie3,
tin3,
2 letter words:
ef5,
fe5,
if5,
en2,
er2,
et2,
in2,
it2,
ne2,
re2,
ti2,