sheep
sheep
policeman
policemen
man
men
moose
moose
thief
thieves
leaf
leaves
child
children
fish
fish
deer
deer
woman
women
person
people
foot
feet
goose
geese
elf
elves
tooth
teeth
mouse
mice
louse
lice
cactus
cacti
tuna fish
tuna fish
octopus
octopi, octopuses