s apostrophe, genitive s
How to spell words with apostrophes correctly
We always add -s with an apostrophe in English.
- Ronny's brother
1. Singular
Add 's to the noun.
- Mandy's brother John plays football.
- My teacher's name is ...
2. Plural
Add the apostrophe ' to regular plural forms:
- The girls' room is very nice.
- The Smiths' car is black.
Add 's to irregular plural forms:
- The children's books are over there.
- Men's clothes are on the third floor.
If there are multiple nouns, add 's only to the last noun:
- Peter and John's mother is a teacher.
If there are multiple nouns that refer to one person/thing – add 's to the last noun.
- Peter and John's mother is a teacher.
If there are multiple nouns that refer to more persons/things – add 's to both nouns.
- Susan's and Steve's bags are black.
3. Singular names ending in -s
Although it is not considered to be good English, you may add only the apostrophe words ending on unpronounced -s
- Charles's dog – Charles' dog
- Illinois's capital – Illinois' capital
Words ending in -x and -z follow the same rules.
- Felix's car – Felix' car
But there are situations where only 's is the best choice to make the meaning clear.