8 letter words:
tirrivie11,
7 letter words:
riftier10,
5 letter words:
fiver11,
firer8,
firie8,
freit8,
frier8,
refit8,
rifer8,
rifte8,
river8,
rivet8,
treif8,
trier5,
4 letter words:
five10,
fier7,
fire7,
fret7,
frit7,
reft7,
reif7,
rife7,
rift7,
rive7,
terf7,
tref7,
vert7,
vier7,
vire7,
vite7,
rite4,
tier4,
tire4,
tirr4,
trie4,
3 letter words:
eft6,
erf6,
fer6,
fet6,
fie6,
fir6,
fit6,
ref6,
rev6,
rif6,
tef6,
vet6,
vie6,
err3,
ire3,
rei3,
ret3,
rit3,
tie3,
2 letter words:
ef5,
fe5,
if5,
er2,
et2,
it2,
re2,
te2,
ti2,