Breakdown of Se, mitä meidän täytyy karsia, on melu.
olla
to be
se
it / he / she (of a person) / that
me
we
täytyä
to have to
Questions & Answers about Se, mitä meidän täytyy karsia, on melu.
Why do we need se at the beginning of the sentence?
This is the pseudo-cleft structure you are currently learning. While English just says 'What we must eliminate...', Finnish typically uses a demonstrative pronoun as an anchor or placeholder in the main clause. You can think of it literally as 'That, which we must eliminate, is noise.' Here, Se acts as the subject for the main verb on.
Why is the relative pronoun in the partitive form (mitä) rather than the nominative (mikä)?
The relative pronoun acts as the object of the verb karsia (to eliminate or prune) within the subordinate clause. Because the thing being eliminated, melu (noise), is an abstract, uncountable mass noun, the action requires a partitive object. Therefore, the relative pronoun representing it must also take the partitive case.
Why is the subject meidän in the genitive case instead of just me?
This is a quick refresher on necessity structures! The verb täytyy (must) is an impersonal necessity verb. It always stays in the third-person singular and requires its logical subject to be in the genitive case, which is why we use meidän instead of me.
Why are there commas around mitä meidän täytyy karsia?
Finnish punctuation rules are very strict about separating clauses. The relative clause mitä meidän täytyy karsia is embedded directly into the middle of the main clause (Se ... on melu). You must use commas on both sides of a relative clause to set it apart from the main clause.