Answer:
Subjects: “Mary” and “I”
Verbs: “washed” and “waxed”
Step-by-step explanation:
A subject is a noun or pronoun that performs the main action in a sentence or the one that is being described or dealt with. A verb is a word indicating an action, state or condition of a subject. In the sentence, “Mary and I” are the subjects because they are performing the main action, which it's “washed” and “waxed” (these words indicate actions).