The article is devoted to the issues of communicative syntax, namely the problems of ellipsis, the identification of criteria for ellipticity. The aim of this article is to identify the communicative potential of elliptical sentences, their prevalence in the speech of the characters of a work of art, as well as to identify their stylistic functions and grammatical features. The status of colloquial speech in general and German colloquial speech in particular, the concept of the norm and the criteria of normativity are considered. The article attempts to define and systematize the types of elliptical sentences, their syntactic features and communicative functions in colloquial speech. The data of practical researches are considered. An ellipse is defined as a violation of the mandatory compatibility within a syntactic construction. Based on the criterion of dependence of elliptic sentences on the context, a classification of ellipses is proposed as contextually conditioned and contextually unconditioned (situational). In question-and-answer units, ellipses perform communicative functions: question, answer, motivation, emotional evaluation, questioning. Elliptic sentences are more connected to the context than full sentences, and from this point of view they are synsematic. The analysis showed that ellipses are divided into two large groups in relation to which member of the sentence implies an unrealized valency: main or secondary. In elliptical sentences, one or both of the main members of the sentence may be missing. In the group of a compound predicate, both the nominal and the main part can be omitted, while the omission of the latter occurs almost twice as often. The article gives practical recommendations to German language teachers on how to use the patterns of constructing elliptical sentences when teaching dialogic speech.