The keyword term functions grammatically as a noun phrase. In this construction, the word "Pentagon" serves as the head noun, which is the core component of the phrase. The preceding elements, "September 11th," act as an adjectival modifier, specifying the particular context or event associated with the noun. The entire phrase collectively names a specific subject: the Pentagon building in the context of the events of that date.
A detailed grammatical analysis reveals that "September 11th" is a proper noun (the name of a date and a historical event) used attributively. When a noun modifies another noun, it is known as a noun adjunct or an attributive noun. It functions like an adjective, providing descriptive detail. In this case, "September 11th" specifies which aspect or moment in the history of the Pentagon is the subject of discussion. This structure, [Noun Adjunct] + [Head Noun], creates a compound idea that is more specific than either component alone.
Recognizing the term as a noun phrase is crucial because it establishes the article's focus on a specific entity and event. This classification dictates that the main point will be descriptive or analytical, centered on a person, place, thing, or idea, rather than on an action (verb) or a quality (adjective). Consequently, the article will be structured to provide information about the Pentagon as it relates to the September 11th attacks, treating this combined concept as its central subject.
