bathe
cache
fiche
lathe
niche
ruche
tithe
... among others
I think they wanted three letters total. If so:
grep '^.he$' /usr/share/dict/words | nl
1 che
2 rhe
3 she
4 the
a three letter word is bug. Three letter words ending with the letter g are bug and hug.
The three-letter word for scull is "oar."
A three-letter word ending in "ux" is "lux," which means a unit of illumination or light.
who
boa
Some three letter words ending in AT are:batcateatfathatmatpatoatpatratsattatvat
eta
too
you, emu, gnu
suq
tar
fra