ACT® · English: Punctuation Conventions
Possessives of Plural and Irregular Plural Nouns
Form the plural noun first, then add the apostrophe. Regular plurals already ending in s just get an apostrophe after that s; irregular plurals with no s get apostrophe plus s.
The test rewards a fixed two-step habit: plural first, possessive second. Never guess where the apostrophe goes by ear. Ask what the plural of the noun is, write that down, then look at its last letter. If the plural already ends in s, like students or the Joneses, tack on just an apostrophe: students' lockers, the Joneses' porch. If the plural does not end in s, because the noun is irregular, like women, children, geese, or men, add apostrophe plus s: women's, children's, geese's, men's.
This is why 'the childrens' toys' is wrong: children is already the plural of child, and it does not end in s, so the possessive needs apostrophe-s, giving children's. Compare students, whose plural ends in s, so the possessive is students' with the mark after the s that's already there. Same mechanism, opposite-looking result, because the two plurals are built differently.
A sneaky case: a family name used as a plural. The Smiths live in the house, not 'the Smith's' live there, because no apostrophe is needed just to show more than one Smith. The apostrophe only shows up if something belongs to them: the Smiths' farmhouse. This topic sits next to the broader punctuation unit's joint-marks, since an apostrophe here is never doing the job of a comma or semicolon joining clauses. Keep the two jobs separate: apostrophes mark possession or contraction, never clause breaks.
Key terms
- possessive
- A noun form showing ownership, usually built with an apostrophe and sometimes an added s.
- regular plural
- A plural formed by adding s or es to the singular noun, like students or Joneses.
- irregular plural
- A plural that doesn't end in s, formed by changing the word itself, like children or geese.
- apostrophe placement
- Where the mark goes relative to the final s, decided only after the plural form is settled.
Watch it explained
- How it worksHow do you form the plural first and only then decide where the apostrophe lands?
- Worked exampleWalk me through writing the possessive of women, then of teachers, then of the Joneses.
- Common mistakeWhy isn't 'the Smith's house' correct when a whole family named Smith lives inside it?
- Common mistakeWhy doesn't an irregular plural such as geese take the apostrophe in the same spot that dogs does?
Check yourself
End of topic.