This paper talks about specific sentence structures in contemporary Serbian language that are a transition between simple and complex sentences, since they contain two finite forms of the verbs (e.g. To je da poludiš; Smisao pravde leži u tome da krivci budu kažnjeni), that however are a functionally - semantically unique predicate only when occurring together. At the position of the second part of the predicate phrase, there is a clause with a subordinate conjunction as its semantic core. Some types of the connective verbs are described, which have a specific role to connect subject argument and its related content or to mark the content of the sentence with a specific modality.