4 letter words:
keef11,
kerf11,
keet8,
reek8,
trek8,
feet7,
fere7,
fete7,
free7,
fret7,
reef7,
reft7,
tref7,
rete4,
tree4,
3 letter words:
kef10,
eek7,
eke7,
eft6,
fee6,
fer6,
fet6,
ref6,
ere3,
ree3,
ret3,
tee3,
2 letter words:
ef5,
fe5,
er2,
et2,
re2,