b) box – boxes                 church – churches  

    brush – brushes           class - classes    

    buzz - buzzes

Final –es is added to nouns that end in –ch, -sh, -ss, and -z

c) baby – babies               party – parties

    city – cities                    poppy – poppies

Words ending in consonant + y take –ies as a plural suffix.

d) man - Men

Foot- feet

Ox – oxen

Tooth – teeth

These nouns have irregular forms, so there is no specific rule.

    Woman     -

women

Mouse    -

Mice

    Child         -    

Children

Goose    - 

Geese

e) echo – echoes                          potato – potatoes

    hero – heroes                            tomato – tomatoes

Some nouns ending in –o take final ­–es.

f) auto- autos               photo- photos       studio – studios

   ghetto-ghettos          piano- pianos       tattoo- tattoos

   kilo- kilos                   radio –radios        video – videos

   memo-memos           solo- solos            zoo- zoos

   soprano – sopranos

   kangaroo- kangaroos

Only the final –s is added to some nouns ending in – o

g) memento – mementoes/ mementos

    volcano-  volcanoes/ volcanos

    zero – zeroes/ zeros

    mosquito- mosquitoes/ mosquitos

    tornado – tornadoes/ tornados

It is possible to add –es or –s to nouns in this category.

h) calf –calves      life – lives         thief- thieves

    half – halves     loaf- loaves       wolf – wolves

    knife- knives     self- selves       scarf – scarves

    shelf – shelves

Some nouns that end in –f or fe are changed to – ves to form the plural.

i)  belief – beliefs                            cliff- cliffs

    chief – chiefs                              roof – roofs

Some nouns ending in –f are not changed and simply – s is added to form the plural.

j) deer – deer        series – series    means - means 

   fish -   fish         sheep – sheep     shrimp – shrimp

   offspring- offspring  

   species – species

Some nouns have the same singular and plural form.

k) criterion – criteria     phenomenon- phenomena

l) cactus – cacti/ cactuses                nucleus – nuclei

   fungus- fungi                                  stimulus – stimuli

   syllabus- syllabi/ syllabuses

m) formula – formulae/ formulas

     vertebra – vertebrae

n) appendix – appendices/ appendixes

    index- indices/ indexes

o) analysis – analyses            basis – bases

    crisis – crises                      hypothesis- hypotheses

    oasis – oases                      thesis- theses

    parenthesis – parentheses

p) bacterium – bacteria           curriculum – curricula

    datum – data                        medium – media

    memorandum – memoranda

Some nouns that English has borrowed from other languages have foreign plurals.