mono
mate
mull
miss
make
meet
meek
mean
mass
mars
mine
math
mutt
made
mace
maze
main
mane
Rue.
add
Aqi
obi
Some 3 letter words with the letter "r" in the middle are: are, bra, bro, arm, url, and ere.
amo
see see
pig
Bay
Mud, bud, dud...and lots more.
ers, urs
Fat.