Predicate Nominative

Can somebody tell me what a Predicate Nominative is and give me
a Sentence Example?

Thanks.

It is the subject (i.e. noun or pronoun), only renamed. It’s grammatically the same as the subject too. It follows a linking verb (not usually “to be,” but can be)

Latin is an old language and it is not spoken as much as it used to be.

Language and it act as predicate nominatives.