Beginner 📐 Grammar · #205 of 305

Plural Nouns Ending in -o

Some nouns take -es, others just -s.

Examples

  • potato → potatoes
  • photo → photos

Key rules

  • Many nouns ending in -o add -es (potato, tomato, hero, echo)
  • Most add -s (photo, piano, radio, zoo)
  • Some allow both (mosquitoes or mosquitos)

Common mistakes

  • photoes → photos
  • tomatos → tomatoes
💡 Tip: Learn the short -es list; treat all others as -s.
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Related Beginner topics

See all Beginner grammar lessons →

Nouns: Naming Words

A noun names a person, place, thing or idea.

Singular and Plural Nouns

Add -s to most nouns; add -es after s, x, ch, sh.

Irregular Plurals

Some nouns change form instead of adding -s.

Countable and Uncountable Nouns

Countable nouns can be counted; uncountable ones cannot take a/an or plural.

Proper and Common Nouns

Proper nouns name specific things and start with a capital letter.

Subject Pronouns

I, you, he, she, it, we, they replace the subject.