A predicate nominative is a noun or pronoun that renames the subject of the sentence. A predicate adjective is an adjective or a word that describes the subject.
Examples of predicate nominative:
1. Mr. Santos is the president of the school.
subject: Mr. Santos
linking verb: is
predicate nominative (noun): president
–We ask: Who is Mr. Santos? (ans: president)
Who is the president? (ans: Mr. Santos)
Therefore president renames Mr. Santos/
2. The person to look for is he.
subject: person
linking verb: is
predicate nominative (pronoun): he
— We ask: Who is the person to look for? (ans: he)
Who is he? (ans: the person to look for)
Therefore he renames person.
Example of predicate adjective:
1. Karen is pretty.
subject: Karen
linking verb: is
predicate adjective: pretty (Pretty describes Karen.)
Notice that both predicate nominative and predicate adjective come after a linking verb..