The increased interest in the analysis of human verbal behavior leads to the need to define a basic unit of the communication sphere which could serve as the basis of its analysis. The first part of the article provides an overview of different speech units proposed by various authors, such as a speech act (J. Austin and J. Searle), speech genre (M. Bakhtin), situational, aspect and parametric model of communicative behavior (I. Sternin), speech action pattern (K. Ehlich und J. Rehbein).