Thematic equative

In systemic functional grammar, a thematic equative is a thematic resource in which two or more separate elements in a clause are grouped together to form a single constituent of the theme-plus-rheme structure.

An example of this is: Here, the theme—the grammatical point of departure—is in bold text; it announces at the start to the listener or reader what the message will be about—the writer's or speaker's angle ("I'm going to tell you what they need for breakfast").

This type of clause sets up the theme-plus-rheme structure in the form of an equation, where theme = rheme.

[1] A thematic equative allows for all possible parts of a clause to be shifted to the start, to be the theme, so that the message can be structured in whatever way the speaker or writer wants.

[2] A unique feature of the thematic equative is its conveying of a meaning of exclusiveness in the rheme.