Although the universal language in Threshold is Common, the community is a diverse mixture of numerous races of humanoids, each with their own racial language. This allows for an interesting element of RP and adds flavor to a multi-layered world.
With this command, you speak in your racial tongue. Since you are used to speaking in the common tongue, this language is a little more strenuous tospeak in, and thus it uses 1 sp (spell point) per statement.
If you have learned to speak other languages (this is much more difficult than simply being able to understand a language), you may use the alternate syntax in order to speak in languages other than your own race language.