English Irregular Plural Nouns Regular Plural Forms The majority of English count nouns are regular and predictable in the spelling of the plural form. Add -s to the end of the singular form or -es to those singulars that end in a sibilant sound (/s/, /z/, /ts/, /dz/). -s -es boy boys horse horses bed beds edge edges book books patch patches pencil pencils prize prizes day days box boxes However, if the singular ends with -y and the -y is not preceded by a vowel (or is not a proper name) the -y changes to -i and the plural is then -es. -y becomes -ies -y becomes -ys spy spies osprey ospreys poppy poppies bay bays penny pennies Germany Germanys Outside of this pattern, however, are several nouns, which are irregular in their spelling. Below is a semi- comprehensive list compiled from various sources. Irregular Plural Nouns - List One Some nouns that end in -f or -fe are changed to -ves in the plural: -f or -fe becomes -ves calf calves scarf scarves elf elves self selves half halves sheaf sheaves hoof hooves shelf shelves knife knives thief thieves leaf leaves wife wives life lives wolf wolves loaf loaves Retrieved from the Internet 14 September 2004 Page 1 http://www.gsu.eduk/~wwwesl/egw/crump.htm#Top 2/11/05 bh 015 Irregular Plural Nouns - List Two Some nouns change the vowel sound in becoming plural: singular plural singular plural fireman firemen man men foot feet mouse mice goose geese tooth teeth louse lice woman women Some Old English plurals are still in use: singular plural child children ox oxen Irregular Plural Nouns - List Three Some nouns ending in -o take -s as the plural, while others take -es. -o becomes -os -o becomes -oes auto autos pro pros echo echoes kangaroo kangaroos solo solos embargo embargoes kilo kilos soprano sopranos hero heroes memo memos studio studios potato potatoes photo photos tattoo tattoos tomato tomatoes piano pianos video videos torpedo torpedoes pimento pimentos zoo zoos veto vetoes Some nouns ending in -o take either -s or -es: singular plural singular plural buffalo buffalos/buffaloes no nos/noes cargo cargos/cargoes tornado tornados/tornadoes halo halos/haloes volcano volcanos/volcanoes mosquito mosquitos/mosquitoes zero zeros/zeroes motto mottos/mottoes Retrieved from the Internet 14 September 2004 Page 2 http://www.gsu.eduk/~wwwesl/egw/crump.htm#Top 2/11/05 bh 015 Irregular Plural Nouns - List Four singular plural Some nouns do not change at all: cod* cod* deer deer fish* fish* offspring offspring perch* perch* sheep sheep trout* trout* *Notice that these are names of fish. Many (but not all!) fish have irregular plural forms. Salmon, pike, halibut and tuna are further examples, but one shark becomes two sharks. These include nouns that are traditionally plural, but are also used for singular forms: singular plural barracks barracks crossroads crossroads dice/die dice gallows gallows headquarters headquarters means means series series species species Irregular Plural Nouns - List Five singular foreign plural English plural in use alga algae amoeba amoebae amoebas antenna antennae antennas formula formulae formulas larva larvae nebula nebulae nebulas vertebra vertebrae Other nouns retain foreign plurals. Note that some of these have adapted a regular English plural form as well. Retrieved from the Internet 14 September 2004 Page 3 http://www.gsu.eduk/~wwwesl/egw/crump.htm#Top 2/11/05 bh 015 Nouns ending in -us with plural -a (only in technical use): singular plural corpus corpora genus genera Nouns ending in -us with plural -i: singular foreign plural English plural in use alumnus alumni bacillus bacilli cactus cacti cactuses focus foci fungus fungi funguses nucleus nuclei octopus octopi octopuses radius radii stimulus stimuli syllabus syllabi syllabuses terminus termini Nouns ending in -um with plural -a: singular Foreign plural English plural in use addendum addenda bacterium bacteria curriculum curricula curriculums datum data erratum errata medium media memorandum memoranda memorandums ovum ova stratum strata symposium symposia symposiums Nouns ending in -ex, -ix becoming plural -ices: singular Foreign plural English plural in use apex apices apexes appendix appendices appendixes Retrieved from the Internet 14 September 2004 Page 4 http://www.gsu.eduk/~wwwesl/egw/crump.htm#Top 2/11/05 bh 015 cervix cervices cervixes index indices indexes matrix matrices matrixes vortex vortices Nouns ending in -is becoming -es in plural: singular plural analysis analyses axis axes basis bases crisis crises diagnosis diagnoses emphasis emphases hypothesis hypotheses neurosis neuroses oasis oases parenthesis parentheses synopsis synopses thesis theses Nouns ending in -on becoming -a: singular plural criterion criteria phenomenon phenomena automaton automata Other irregular plurals, retained from different languages: singular plural libretto libretti Italian tempo tempi virtuoso virtuosi cherub cherubim Hebrew seraph seraphim Greek schema schemata Retrieved from the Internet 14 September 2004 Page 5 http://www.gsu.eduk/~wwwesl/egw/crump.htm#Top 2/11/05 bh 015.