Final answer:
The sentence 'Es mi tercer año en la universidad' is grammatically correct.
Step-by-step explanation:
The sentence 'Es mi tercer año en la universidad' is grammatically correct.
In this sentence, 'Es' is the subject, which is the pronoun 'it' referring to an unspecified subject. 'mi tercer año' is the complement, meaning 'my third year'. 'en la universidad' is a prepositional phrase indicating 'at the university'.
Therefore, the sentence is grammatically correct because it has a clear subject and the components of the sentence are structured correctly.
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