5 letter words:
peter7,
4 letter words:
pfft12,
teff10,
feet7,
fere7,
fete7,
free7,
fret7,
reef7,
reft7,
tref7,
peer6,
pere6,
pert6,
pree6,
rete4,
tree4,
3 letter words:
eff9,
eft6,
fee6,
fer6,
fet6,
ref6,
pee5,
per5,
pet5,
rep5,
ere3,
ree3,
ret3,
tee3,
2 letter words:
ef5,
fe5,
pe4,
er2,
et2,
re2,