About Slovak
Slovak is an Indo-European language that belongs to the West Slavic languages (together with Czech, Polish, Silesian, Kashubian, and Sorbian).

The primary principle of Slovak spelling is the phonemic principle, "Write as you hear". The secondary principle is the morphological principle: forms derived from the same stem are written in the same way even if they are pronounced differently. An example of this principle is the assimilation rule (see below). The tertiary principle is the etymological principle, which can be seen in the use of i after certain consonants and of y after other consonants, although both i and y are pronounced the same way. Finally there is the rarely applied grammatical principle, under which, for example, there is a difference in writing (but not in the pronunciation) between the basic singular and plural form of masculine adjectives.

Source: Wikipedia