For example, in this Russian sentence:
the inflection of the noun indicates its instrumental role the nominative перо changes its ending to become пером. Modern English, lacking an instrumental case, might use a preposition (usually with) to express the same meaning:
However, such a sentence structure is often altogether avoided in English by transforming the noun into a past-tense verb, e.g. "I penned the book." Technical descriptions often use the phrase "by means of", which has often conventionally been replaced by "via", which is a Latin instrumental ablative of the nominative (with the same form) via, meaning road, route, or way. In the ablative this means by way of.
The instrumental case appears in Old English, Georgian, Basque, Sanskrit, and the Balto-Slavic languages. An instrumental/comitative case is arguably present in Turkish and other Altaic languages, as well as in Tamil. Also, Uralic languages reuse the adessive case where available, or locative case if not, to mark the same category. For example, the Finnish kirjoitan kynällä does not mean "I write on a pen", but "I write using a pen", even if the adessive -llä is used. In Ob-Ugric languages, the same category may also mark agents with verbs that use an ergative alignment, like "I give you, using a pen".
The instrumental case is most notably used in Russian, where the case is called творительный падеж (tvoritelnij padezh). Though exceptions exist, the instrumental case in Russian can generally be distinguished by the -ом ("-om") suffix for most masculine and neuter nouns, the -oй ("-oy") suffix for most feminine nouns and -ами ("-ami") for either gender in the plural.
However, in Russian, as with many Slavic languages, the instrumental case is not only used to denote the mean of a certain action, but also:
Though the instrumental case does not exist in many languages, some languages use other cases to denote the means, or instrument, of an action. In Classical Greek, for example, the dative case is used as the instrumental case. This can be seen in the sentence "..με κτείνει δόλῳ," or "..me ktenei dolôi" (Book IX, line 407 of the Odyssey), which means "he kills me with a bait." Here, "δόλῳ," the dative of "δόλος" ("dolos" - a bait) is used as the instrumental case (the mean or instrument here is, obviously, the bait). In Latin, the ablative case is used, as in oculīs vidēre, "to see with the eyes".
Obama's Climate Adviser Plans to Step Down (Posted 2013-10-08 02:01:42) ; Zichal Played an Instrumental Role in Pushing for Stricter Fuel Efficiency Standards for Automobiles
Oct 08, 2013; The White House's senior energy and climate adviser, Heather Zichal, is leaving the administration, officials said Monday,...