5 letter words:
fermi10,
fiere8,
4 letter words:
feme9,
ferm9,
firm9,
feer7,
fere7,
fier7,
fire7,
free7,
reef7,
reif7,
rife7,
emir6,
meer6,
mere6,
meri6,
mire6,
riem6,
rime6,
3 letter words:
fem8,
erf6,
fee6,
fer6,
fie6,
fir6,
ref6,
rif6,
eme5,
mee5,
mir5,
rem5,
rim5,
ere3,
ire3,
ree3,
rei3,
2 letter words:
ef5,
fe5,
if5,
em4,
me4,
mi4,
ee2,
er2,
re2,