The Genitive Case (-n)
To show ownership in Finnish, use the genitive case. This works like the English "'s" (e.g., "the dog's"). Add the suffix -n to the owner noun, and place the owner right before the thing being owned.
Stem Changes in the Genitive
Adding -n closes the final syllable, which often triggers consonant gradation in the word stem. For example, a double consonant might weaken to a single consonant (like the tt in tyttö becoming a single t in tytön), or a t might soften to a d (äiti becoming äidin).
For nouns ending in -e (like perhe), the final -e doubles before adding the -n.
Linking Attributes and Details
Use the genitive case to connect people, places, or objects to details like their address, age, profession, or price.
The Owned Object in Different Cases
The owner always stays in the genitive case, but the thing being owned can still change its case depending on its role in the sentence. For example, if the owned thing is the object of a negative sentence or used with a verb like kysyä (to ask), it takes the partitive case.
