Y. J. Doran - The Discourse of Physics: Building Knowledge through Language, Mathematics and Image

• Structuring

Presence of Functions in the structure: the presence of a Function in a Function structure is specified by inserting the Function into the structure; the operation of insertion is symbolised by +; e.g. + Subject and + Mood.

Functional constituency relations: two Functions may be related by constituency and to specify this constituency relationship in the Function structure one Function is expanded by the other; the expansion is symbolised by putting the expanding constituent Function within parenthesis, e.g. Mood (Subject), which means that Mood is expanded to have Subject as a constituent Function. A Function may be expanded by more than one other Function, e.g. Mood (Subject, Finite).

Relative ordering of Functions and ordering relative to unit boundaries: two Functions may be ordered relative to one another in the Function structure and this relative ordering is symbolised by the ^; e.g. Subject^Finite, Mood^Residue. The ordering may also be relative to the left or right boundary of a grammatical unit (represented by #), e.g. #^Theme, meaning the Theme occurs at the beginning of the unit, and Moodtag^# meaning the Moodtag occurs at the end of the unit.

A distinction can be made between sequencing Functions directly after one another, e.g. Subject^Finite, and sequencing Functions with respect to one another, e.g. Subject Finite (meaning that the Subject comes before the Finite but that another Function, for example, a Mood Adjunct, might intervene). Interrupting a function involves placing one Function within another Function, such as placing a hypotactic beta clause within an alpha clause in <<>>.

Subclassification of a Function: one Function can be subclassified into two or more different Functions, i.e. the subclassified Function is a less delicate generalisation of the Functions subclassifying it. Subclassification is indicated by a subscript, where the subclassifying Function is the subscript of the more general Function, e.g. ResultNumerical indicates that Numerical subclassifies Result

• Layering

Conflation of one Function with another: one Function from one perspective is conflated with a Function from another perspectivei.e. the two Functions are specific as different layers of the same constituent. They are identified with one another. Conflation is symbolised by /; for example, Subject/Agent means that Subject (interpersonal) and Agent (ideational) apply to the same constituent.

• Inter-Rank Realisation

Realisation of a Function in terms of features from the rank below: the realisation of a Function in a Function structure is stated by preselecting one of more features from the unit realising it; preselection is symbolised by :, e.g. Subject: nominal group and Finite and Predicator: verbal group.

A distinction can be made between the realisation of a Function through a feature (formalised as Function: feature) and lexicalisation of a Function through a specific lexical item (e.g. formalised for English optatives as Subject Lets ). Embedding can be defined as the realisation of a Function through a feature from the same or higher rank.