Robin's Nest
Do you know or remember this series, Robin's Nest?

In English, showing that something belongs to someone or something can sometimes be tricky for learners, especially for Spanish speakers. In Spanish, we typically use the preposition de (e.g., el coche de Juan), but English frequently uses a special structure known as the Saxon genitive (or possessive 's)[cite: 1].

Understanding when and how to use the Saxon genitive is essential for natural-sounding speech and writing. Let's break down the rules, structure, and common exceptions.

What is the Saxon genitive?

The Saxon genitive is formed by adding an apostrophe and an s ('s) or just an apostrophe (') to a noun to indicate possession or a relationship.

  • This is Peter's book. (Este es el libro de Peter.)
  • That is my sister's car. (Ese es el coche de mi hermana.)

Basic rules for forming the possessive

  1. Singular nouns: Add 's to singular nouns, even if they already end in -s (though both options are acceptable for names ending in s).

    • The teacher's desk is near the window.
    • James's dog is very friendly. (or James' dog)

  2. Regular plural nouns: If a plural noun already ends in -s, simply add an apostrophe (') at the end.

    • The students' marks were impressive.
    • My parents' house is in Valencia.

  3. Irregular plural nouns: For plural nouns that do not end in -s, add 's.
    • The children's playground is safe and clean.
    • Women's clothes are on the second floor.

Special cases & advanced rules

1. Joint vs. individual possession

When two or more people own something together, add 's only to the last name. If they own things separately, add 's to each name.

  • Mark and Sarah's apartment is spacious. (They share one apartment.)
  • Mark's and Sarah's cars are parked outside. (They each have their own car.)

2. Inanimate objects: 's vs. of

As a general rule, we use the Saxon genitive for people, animals, and time expressions, while we use of for non-living objects.

  • The cat's tail was twitching. (Living being)
  • The leg of the table is broken. (Inanimate object — NOT the table's leg)
  • Yesterday's news was surprising. (Time expression)

3. Places of business and homes

We often omit the noun following 's when referring to shops, services, or someone's home.

  • I bought some bread at the baker's. (= at the baker's shop)
  • We had dinner at Mary's last night. (= at Mary's house)

Key vocabulary words

  • Possession (noun) - The state of having, owning, or controlling something.
    "Clear possession rules make English writing far more natural."
  • Inanimate (adjective) - Not alive; showing no sign of life.
    "Inanimate objects generally take 'of' rather than the Saxon genitive."
  • Joint (adjective) - Shared, held, or done by two or more people together.
    "They bought a joint ticket to the exhibition."

Recommended reading & resources