Nominative (Subject) is the form of a noun, a pronoun or an adjective when it is the subject of a verb. Marking typically the subject of a verb especially in languages that have relatively full inflection. A noun, pronoun or an adjective in nominative case is the subject. The subject is the doer of the action , the one that carries out the action or the one being described. Take a look at this chart; observe the words that identifies the subject in a sentence.