1. Words ending in -O
Use ending -es if a noun ends in -o.
- Examples: potato - potatoes, tomato - tomatoes.
But: add only -s to words of foreign origin or abbreviated words ending in -o.
- Examples: piano - pianos (short from fortepiano), photo - photos (short from photograph)
2. Words ending in -Y
If a noun ends in -y that is preceded by a consonant, change the -y to -i and add -es.
- Examples: baby - babies, story - stories.
But: if -y follows a vowel, just add -s.
- Examples: day - days, boy - boys.
3. Words ending in -F or -FE
Some nouns that end in -f or -fe change the -f or -fe to -v and add -es.
- Examples: knife - knives, wolf - wolves
But: some other nouns ending in -f or -fe just add -s.
- Remember: handkerchief - handkerchiefs, safe - safes, cliff - cliffs.
4. Irregular Plural Nouns
Names of some creatures do not change their forms in plural.
Remember plural forms of the following words:
fish - fish
deer - deer
sheep - sheep