No highlighter or focus particle is used in cleft construction. A focused noun phrase is marked in the verb, in that it gets a different inflection, typical for subordinate clauses, than in main clauses. The difference can be illustrated with the contrasting sentences translated as 'He
catches the ball' (main clause verb; so-called independent order) and 'It is him who catches' or 'He is the catcher'.
Wiya kaashchitin-eew la plot.
[he catch-3SBJ.3OBJ the ball]
Wiya kaa-kawshchitin-iwee-t
[he REL-catch-INDF.OBJ-3]
Intuitively a construction with a copula sounds plausible, but we have no example in our data.
Source: Laverdure and Allard 1983: 62