5 letter words:
perks11,
perps9,
preps9,
repps9,
4 letter words:
keps10,
perk10,
skep10,
spek10,
erks8,
peps8,
perp8,
prep8,
repp8,
serk8,
sker8,
reps6,
3 letter words:
kep9,
erk7,
pep7,
per5,
pes5,
pre5,
rep5,
ers3,
res3,
ser3,
2 letter words:
pe4,
er2,
es2,
re2,