Plural

The plural form of a countable noun refers to the fact there is more than one. Mass nouns are not usually used in plural.

Regular plurals

 * we usually add -s:
 * pronounced /s/: book - books; night - nights;
 * pronounced /z/: friend - friends; eye - eyes;


 * -es to words ending in -ch/-x/-s/-sh: watch - watches; box - boxes; glass - glasses; dish - dishes;


 * -ies to words ending -y: cherry - cherries; sky - skies;


 * Words ending in -o
 * Add -es: hero - heroes; potato - potatoes; tomato - tomatoes;
 * Add -s: piano - pianos; radio - radios; video - videos;

See Pronunciation of the morpheme “-s”.

Irregular plurals
For historical reasons a few plurals are irregular.


 * No plural. Usually animals - sheep, swine, deer.


 * Ending in -ves for some words ending –f/fe: half - halves; knife - knives; life - lives; loaf - loaves; shelf - shelves; wife - wives; but note the following: beliefs, chiefs, gulfs, proofs, roofs. The plural of dwarf can be dwarfs or dwarves.


 * Ending in /ðz/ for some words ending in /θ/: baths; paths; youths
 * Both a regular /θs/ and an irregular /ðz/ plural exist: oaths, truths, wreaths


 * others: child – children /tʃaɪld - ˈtʃɪldrən/; foot - feet /fʊt - fiːt/; goose - geese /ɡuːs - ɡiːs/; house - houses /ˈhaʊs - ˈhaʊzɪz/; louse - lice; man – men; mouse - mice; ox - oxen; tooth – teeth; woman - women /ˈwʊmən - ˈwɪmɪn/;


 * Plural is different only in written form: chairman - chairmen /ˈtʃeərmən/; milkman - milkmen /ˈmɪlkmən/; postman - postmen /ˈpəʊstmən/


 * Singular and plural are spelled identically, but have a different pronunciation: corps /kɔːr, kɔːrz/


 * Greek plurals: analysis - analyses /əˈnæləsɪs - əˈnæləsiːz/; basis - bases /ˈbeɪsɪs - ˈbeɪsiːz/; crisis - crises /ˈkraɪsɪs - ˈkraɪsiːz/


 * process - processes: This word has a regular plural and irregular ones.
 * American English: /ˈprɒss - ˈprɒssɪz, ˈprɒsəsɪz, ˈprɒsəˌsiːz /;
 * Received Pronunciation: /ˈprəʊss - ˈprəʊssɪz, ˈprəʊsəsɪz/


 * Heteronyms
 * axes /ˈæksɪz/ plural of ax/axe; /ˈæksiːz/ plural of axis
 * bases /ˈbeɪsɪz/ plural of base; /ˈbeɪsiːz/ plural of basis

Mass nouns
Some nouns ending in -s are mass nouns: measles – a news item – mathematics - physics – politics – a TV series;