The general idea of a sequence of sentences forming a text includes two different notions. On the one hand, it presupposes a succession of spoken or written utterances irrespective of their forming or not forming a coherent semantic complex. On the other hand, it implies a strictly topical stretch of talk, i.e. a continual succession of sentences centering on a common informative purpose. It is this latter understanding of the text that is syntactically relevant. It is in this latter sense that the text can be interpreted as a lingual element with its two distinguishing features: first, semantic (topical) unity, second, semantico-syntactic cohesion.
The primary division of sentence sequences in speech should be based on the communicative direction of their component sentences. From this point of view monologue sequences and dialogue sequences are to be discriminated.
In a monologue, sentences connected in a continual sequence are directed from one speaker to his one or several listeners. As different from this, sentences in a dialogue sequence are uttered by the speakers-interlocutors in turn, so that they are directed, as it were, to meet one another.
The direction of communication should be looked upon as a deeper characteristic of the sentence-sequence than its outer, purely formal presentation as either a monologue (one man's speech) or a dialogue (a conversation between two parties).
Prospective ("epiphoric", "cataphoric") connection is effected by connective elements that relate a given sentence to one that is to follow it. In other words, a prospective connector signals a continuation of speech: the sentence containing it is semantically incomplete. As different from prospective connection, retrospective (or "anaphoric") connection is effected by connective elements that relate a given sentence to the one that precedes it and is semantically complete by itself. Retrospective connection is the more important type of sentence connection of the two; it is the basic type of connection in ordinary speech.