7 letter words:
fritter10,
6 letter words:
fitter9,
titfer9,
ritter6,
territ6,
triter6,
5 letter words:
firer8,
frier8,
fritt8,
refit8,
rifer8,
tetri5,
titer5,
titre5,
trier5,
trite5,
4 letter words:
fire7,
fret7,
frit7,
reft7,
reif7,
rife7,
rift7,
tref7,
rite4,
tier4,
tire4,
titi4,
tret4,
3 letter words:
eft6,
fer6,
fet6,
fie6,
fir6,
fit6,
ref6,
rif6,
err3,
ire3,
rei3,
ret3,
tet3,
tie3,
tit3,
2 letter words:
ef5,
fe5,
if5,
er2,
et2,
it2,
re2,
ti2,