Any natural language text may be exhaustively divided up into clauses and “extra-clausal constituents” (ECCs). ECCs are not part of the clause proper, but more loosely associated with it in ways which can most adequately be described in terms of pragmatic functionality.
- Dik (1989), Pag. 264

ECCs have the following properties: •They may precede, interrupt, or follow the clause proper; •They are typically “bracketed off” from the clause by pause-like inflections in the intonation pattern; •They are not sensitive to the clause-internal grammatical rules, though they may entertain relations of coreference, parallelism (e.g. same case marking), or antithesis (e.g. negative Tag with positive clause) with the clause they are associated with. •They are not essential to the integrity of the internal structure of the clause: when they are left out, the remaining clause structure is complete and grammatical.
- Dik (1989), Pag. 265