type s for subject, v for verb, pn for predicate nominative, and a for appositive. the math class learned…

Brief Explanations:

The subject is what the sentence is about. Here, "The math class" is what is doing the action, so it's the subject. The verb is the action word, and "learned" is the action. There is no predicate nominative (a noun or pronoun that renames the subject and follows a linking verb, and there's no linking verb here) and no appositive (a noun or noun - phrase that renames another noun right beside it).

Answer:

S. The math class, V. learned