This study represents the initial stage of a twofold effort: to revitalize the NooJ module for Serbian by initiating a new framework for the tagging of temporal expressions, and to enrich the already well-developed Ukrainian module through the creation of grammars for date and time expressions in both languages. This allows us to compare temporal expressions in both languages and identify patterns of concordance, as well as points of divergence. On the one hand, this work aims to enable advanced analysis of temporality-related patterns in literary texts (for example, contrasting expressions of duration with punctual expressions, such as a specific time), and on the other hand, it involves creating grammars of the same phenomena in two languages of the same branch (Slavic) but from different groups (Eastern for Ukrainian, Southern for Serbian), allowing for a closer examination of their differences (for instance, the use of an ordinal number in certain temporal expressions in Ukrainian, whereas a cardinal number is used for the same expression in Serbian). Additionally, this study highlights under-explored similarities, such as paucal numeral phrases with numbers 2, 3, and 4, as well as numbers greater than 20 that end in these digits. These paucal forms determine the case and the number of the nouns and adjectives that follow them, exhibiting inflectional features distinct from both the singular and the plural.