Nominative case is used for both subjects and predicate nouns/pronouns.
check this site.
http://englishplus.com/grammar/00000351.htm
That is correct! Pronouns used as subjects or subject complements are not always in the nominative case. The case of a pronoun depends on its function in the sentence. The three cases of pronouns are nominative (subject), objective (direct or indirect object), and possessive (showing ownership). Therefore, the answer is B) False. Pronouns can be in the nominative case when they function as subjects or subject complements, but they can also be in other cases depending on their role in the sentence.
