NoAMark: The function A is not explicitly marked, while S, P, or both are marked. A is therefore marked with a zero (∅) morpheme.
(1) laura level-et ír.
Laura letter-acc write.prs.3sg
‘Laura is writing a letter.’
(2) laura énekel.
Laura sing-prs.3sg
‘Laura is singing.’
In Hungarian, if the noun is in the A (1) or the S (2) position, it is unmarked, while the (P) takes the accusative suffix (1). From a formal perspective, the grammatical subject (S/A) is identifiable by its nominative case marking and the agreement of verbal suffix (cf. Tolcsvai Nagy 2012, 2013: 283‒312, É. Kiss 2002: 8‒14).