5 letter words:
feers8,
feres8,
frees8,
reefs8,
sefer8,
4 letter words:
feer7,
fees7,
fere7,
free7,
reef7,
refs7,
serf7,
eres4,
rees4,
seer4,
sere4,
3 letter words:
efs6,
erf6,
fee6,
fer6,
fes6,
ref6,
ere3,
ers3,
ree3,
res3,
see3,
ser3,
2 letter words:
ef5,
fe5,
ee2,
er2,
es2,
re2,