5 letter words:
offer11,
reffo11,
preop9,
4 letter words:
prof9,
pepo8,
perp8,
poep8,
pope8,
prep8,
prop8,
repp8,
fore7,
froe7,
orfe7,
pore6,
repo6,
rope6,
3 letter words:
eff9,
off9,
fop8,
pep7,
pop7,
erf6,
fer6,
foe6,
for6,
fro6,
orf6,
ref6,
ope5,
per5,
pre5,
pro5,
rep5,
ore3,
reo3,
roe3,
2 letter words:
ef5,
fe5,
of5,
op4,
pe4,
po4,
er2,
oe2,
or2,
re2,