Final answer:
In the sentence, 'Jerry studies for three hours every day,' the verb 'studies' is a main verb. Main verbs express the main action or state of being in the sentence.
Step-by-step explanation:
In the sentence, 'Jerry studies for three hours every day,' the word 'studies' is the verb you're trying to identify. The verb 'studies' is an example of a main verb because it stands alone and isn't helping another verb express action. Main verbs express the main action or state of being in the sentence. Here, 'studies' is the action that Jerry is doing. So, the correct answer is, 'b. main verb'.
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