EN
The author tries to find out whether the preposition is a word or a morpheme. The material used in the present study represents contemporary spoken Polish. The analysis shows what parts of speech and their grammatical forms are accompanied by Polish prepositions. The article also presents the results of studies of the syntax of prepositional constructions. The author concludes with a suggestion to interpret the preposition as a class of morphemes which modify the meaning and the reaction of verbs determined by prepositional expressions. In this respect, the function of prepositions is similar to that of verb-prefixes.