Which sentence uses a predicate nominative?

Carson often seems distracted.

Through his own efforts he had become our captain.

Rachel's speech was unusually brief.

Leigh's daily commute to her job is exhausting.

The sentence that uses predicate nominative is: Through his own efforts, he had become our captain. Predicate nominative is a word or a group of words that renames or identifies what is being talked about in the sentence. These words usually follow a linking verb. Predicate nominatives only take the form of nouns or pronouns.