thief
thieves
mango
mangoes
phenomenon
phenomena
cactus
cacti
hypothesis
hypotheses
ovum
ova
tax
taxes
analysis
analyses
gosse
geese
moose
moose
datum
data
diagnosis
diagnoses
foot
feet
wife
wives
leaf
leaves
die
dice
woman
women
louse
lice
quiz
quizzes
fish
fish
half
halves
knife
knives
bacterium
bacteria
deer
deer
nucleus
nuclei
allumnus
alumni
fireman
firemen
ox
oxen
tooth
teeth
child
children
mouse
mice
sheep
sheep
person
people
fungus
fungi
wolf
wolves