The Prototypical Instance At The Level Of Form

Fawcett (2010: 41):

The prototypical instance at the level of form is a 'sentence' — and a sentence frequently consists of a single clause, e.g., I've been discussing that new student with Peter. Since the grammar is part of a fuller model for the generation of texts, we may also refer to the output as a text-sentence, and this has the value of reminding us that sentences do not occur singly, as formal linguists sometimes appear to assume, but within longer texts in which they themselves function as elements. (Note, however, that we can also treat a group of words such as that new student as an instance, exactly as is done in the little grammar in Appendix A.)

Blogger Comments:

Here Fawcett confuses the theoretical categories of 'instance' and 'unit'.  In SFL theory, any unit can be construed in terms of both potential and instance, and in terms of both system (paradigmatic axis) and structure (syntagmatic axis).