[…] we must not think of linguistic expressions as isolated objects, but as instruments which are used by a Speaker in order to evoke some intended interpretation in the Addressee, within a context defined by preceding expressions, and within a setting defined by the essential parameters of the speech situation.
- Dik (1989), a pag.13

Linguistic expressions are complex networks, characterized by functional relations operative at different levels.
- Dik (1989), a pag.24

Within verbal interaction, the participants avail themselves of certain instruments which, in a general sense of the term, we shall call “linguistic expressions”. These expressions themselves are again structured entities, i.e. they are governed by rules and principles which determine their build-up. From the functional point of view, then, linguistics has to deal with two types of rule systems, both ratified by social convention: (i) the rules which govern the constitution of linguistic expressions (semantic, syntactic, morphological, and phonological rules); (ii) the rules which govern the patterns of verbal interaction in which these linguistic expressions are used (pragmatic rules).
- Dik (1989), a pag.3