Learn Finnish: He vetivät naruja neljästään sitä mukaa kun näytelmä edistyi. - The four of them pulled the strings as the play progressed.

Neljästään is an adverb meaning 'the four of them' or 'four people together with no one else'. It is formed by taking the number neljä (four), adding the elative case ending -stä, and attaching the third-person possessive suffix -än. This -staan/-stään structure is used to express the exact size of an exclusive group performing an action.

How does the phrase sitä mukaa kun work, and could I just use kun?

While kun simply means 'when' or 'as', the fixed phrase sitä mukaa kun translates to 'at the same rate as' or 'in proportion to'. It emphasizes a continuous, simultaneous progression: they were pulling the strings exactly in time with the play advancing.

Why is the object naruja in the partitive plural instead of the plural accusative?

The action of pulling strings here is ongoing and continuous, rather than a single completed event with a clear endpoint. When an action is continuous (irresultative), the object takes the partitive case (naruja). If they had pulled a specific set of strings once to finish a discrete task, it would be the plural accusative narut.

Is vetivät naruja used idiomatically here like 'pulling strings' in English?