Breakdown of Sääntö toimii vähäisin poikkeuksin.
sääntö
rule
toimia
to function, to work / to act
vähäinen
slight
poikkeus
exception
Questions & Answers about Sääntö toimii vähäisin poikkeuksin.
Why is the instructive case used here instead of a postposition like kanssa for 'with'?
While you could grammatically say vähäisten poikkeusten kanssa, using the instructive case plural (vähäisin poikkeuksin) is the standard, idiomatic way to express 'with [adjective] exceptions' in Finnish. The instructive is frequently used in these types of established adverbial phrases.
How does the adjective vähäinen become vähäisin in this sentence?
Adjectives must agree with their nouns in the instructive case. You form the instructive by taking the plural stem of the word and adding -n. Because vähäinen is a word ending in -nen, its plural stem is vähäisi-. Adding the -n gives us vähäisin.
Is the instructive case always in the plural form, like poikkeuksin here?
Yes, in modern Finnish, the instructive case is almost exclusively used in the plural, which is why it is often called the instructive plural. It attaches to the plural stem (here, poikkeuksi-) even in some fixed expressions where English might translate it as a singular concept.
As a refresher, how do we get the plural stem poikkeuksi- from the basic noun poikkeus?