In the phrase provided, the main point or keyword subject to analysis is "Patriot Day," which functions grammatically as a proper noun. It serves as the predicate nominative, identifying or renaming the subject, "9/11."
The grammatical structure of the sentence is Subject + Linking Verb + Predicate Nominative. The subject is "9/11," a specific date functioning as a noun. The verb is "is," a linking verb that equates the subject with the term that follows it. The term "Patriot Day" is a compound proper noun, which is the specific, official name designated for the annual observance. Although "patriot" can function as an adjective in other contexts (e.g., "a patriot act"), here it is an integral part of the formal title of the day, not a descriptor of the noun "day."
Identifying "Patriot Day" as a proper noun is crucial because this classification confirms its role as a formal title rather than a mere description. This grammatical function establishes a definitive identity for the date of September 11th in an official capacity. The sentence, therefore, is not just describing the day; it is formally defining it by its designated name.
