1. Definition

Focus is often defined as the notion that provides new or salient information in a sentence. Focus typically involves a focus-background articulation. Focus is the "informative" part of the sentence; the background is the "non-informative" part, that is, the knowledge that the speaker presupposes to be shared by the hearer (Halliday 1967; Jackendoff 1972; Vallduví and Engdhal 1996, among others).

There are different uses of focus. New information, in i…