Plural rule for words ending in o?

Answer 1

There is a helpful rule to form the plurals of words ending with o, but there are many words that are rule-breakers!

Follow this guideline for many words:

If it's a music word, simply add s. Examples: piano, pianos cello, cellos alto, altos

If it's not a music word, check the letter in front of the o. If it's a consonant, add -es.

If it's a vowel, add s.

Examples: hero, heroes potato, potatoes hobo, hoboes

rodeo, rodeos Oreo, Oreos

Lots of words break the rule however, and some go either way.

photo, photos

hello, hellos

auto, autos

pimento, pimentos

zero, zeros or zeroes

buffalo, buffaloes, buffalos, or even buffalo