The most prototypical function of locative cases is to indicate location, as the name suggests. However, they are also used in a range of syntactic constructions, much like prepositions in Indo-European languages (e.g. "We're *at* school" vs. "We're good *at* math", in which only the first "at" has a locative meaning). In Finnish, the suffix "-lla" as a locative means "on (top)", but may function to code the idea of "being used as an instrument", e.g. "kirjoitan kynällä" "I write with a pen" (lit. 'I write pen-on').