1. Language Resources for Circumstances

Although circumstances are often expressed as prepositional phrases,

SFL allows many different grammatical resources to realise circumstantial meaning.

These include adverbs, adverbial groups, nominal groups, prepositional phrases, and dependent clauses.

The examples below are based on Earth Science contexts.

Language Resources for Circumstances

Resource type	How it realises a circumstance Example (Earth Science)
Prepositional phrase	Most common form; expresses time, place, manner, cause, etc. Lava cooled after the eruption. Plates collide at the boundary.
Prepositional phrase with embedded nominal group	the noun has a classifier or describer Magma rose through the upper mantle. Ash drifted over the Pacific region.
Adverb	Single-word circumstance, often time or manner Ash spread quickly. The ground shook briefly.
Adverbial group	Expanded adverb expressing degree, manner, or frequency The volcano erupted very suddenly. Tremors occurred quite often.
Nominal group (circumstantial)	A noun group functioning as a circumstance (often time or place) The quake struck last night. The eruption continued all day.
Prepositional phrase with embedded nominal group	A PP whose object is a full NG giving detailed circumstantial meaning Magma rose through the upper mantle. Ash drifted over the Pacific region.
Non-finite clause	-ing or -ed clause functioning as a circumstance (often manner or cause) Flowing rapidly, lava covered the slope. Weakened by heat, the crust fractured.
Finite dependent clause (adverbial clause)	Introduced by when, because, although, if, as, while, etc. The ground shook when the fault slipped. Rock melted because it was heated intensely.
Circumstantial clause of comparison	Clause introduced by as if / as though Ash billowed as if the volcano were breathing.
Circumstantial clause of purpose	Clause introduced by so that / in order that Barriers were built so that waves would be reduced.
Circumstantial clause of concession	Clause introduced by although / even though The volcano remained active even though tremors decreased.
Circumstantial clause of condition	Clause introduced by if / unless Stress builds if plates lock together.