Questions & Answers about Tämä tarina on tärkeä osa sukupuuta.
Why is sukupuuta in the partitive case?
The word osa (part) requires the noun that follows it to be in the partitive case. To say "part of the family tree", you use osa plus the partitive form sukupuuta.
Why is tärkeä osa in the nominative case rather than the partitive?
Although descriptions after the verb olla (to be) are often partitive, they stay in the nominative when describing a singular, countable subject. Since the story is exactly one specific part, tärkeä osa takes the nominative.
How do you add case endings to a compound word like sukupuuta?
Sukupuu is made of suku (family or kin) and puu (tree). When adding case endings to compound words in Finnish, you only decline the final part of the word. Therefore, suku stays the same and puu takes the partitive ending to become puuta.