Direction Of Coding And Agency

A decoding identifying clause can be middle or effective:

but an encoding identifying clause is always effective:

Decoding vs Encoding Interrogatives

'Show' As Material Process Embedded In Encoding Relational Clause

The verb show also serves as a relational or verbal Process.

Blowin' In The Wind

Role As Identifier Value

Clause-Final Subject

Adverbial Group Of Cause Serving As Verbiage And Phenomenon Participants

The "Agency" Of Genes

'Used To'

 The Finite used to conflates the meaning of a temporal Adjunct with past tense:

'As Usual' vs 'Usually'

as usual serves as a comment Adjunct of the type 'predictable'.

See Halliday & Matthiessen (2014: 191).

The Existence Of Words

'Be' As Material Process

'Lead' As Circumstantial Identifying Process

Attribute As Unmarked Theme

Identifying Clause Without Medium (Identified Token)

Descartes' Reification Of Sensing

An Enclosed Structurally Unrelated Clause

Mr Minter, 'Call me Ted', was  a large, untidy, perpetually smiling man with the look of an astute rabbit.

— John Mortimer Rumpole And The Asylum Seekers

One way to analyse the enclosed clause as structurally related is to take the view from below. Because it is realised as its own tone group (TONALITY) and realised by tone concord with what precedes (TONE), the enclosed clause is realised as if it were in non-defining elaborating relationship with the surrounding clause. Such an interpretation, though, requires treating the clause that projected it as ellipsed.

Intense Emotion Without Graduated Affect

This is an experiential construal of intense emotion but not an interpersonal enactment of graduated affect. This is because AFFECT is the system of enacting a positive or negative appraisal by reference to emotion, and no such appraisal is enacted here. (Any enactment of a judgement by the author of the clause is a separate matter.) 

Material Clause Without Medium

Nominal Group As Qualifier