This paper discusses, using Hungarian data, the way universal syntactic principles pertaining to nominal coordinate constructions assert themselves in actual language use. The head (dominant constituent) of coordinative constructions is taken to be the coordinative conjunction. The author argues that coordinative conjunctions perform a double structure building function: they have a 'quantifier' face triggering plurality effects, and a 'pronominal' face having to do with agreement in person, number, definiteness, case, and other types of features. First, two major classes of coordinative conjunctions are distinguished: those of n-ary and binary conjunctions. (The former, but not he latter, may coordinate an arbitrary - i.e., grammatically not restricted - number of constituents and can be applied to any grammatical category that can be coordinated at all.) Next, the double function of n-ary conjunctions in nominal coordinate constructions is presented. After that, special cases of nominal coordination involving quantified or numerically determined constituents are analyzed in which the quantified or numerically determined construction itself reflects the double nature of the coordinative conjunction head. On the basis of empirical analyses, the author tries to confirm his hypotheses concerning these conjunctions.