September 11th Special Day
The keyword phrase "september 11th special day" functions grammatically as a noun phrase. The core element, or head, of the phrase is the noun "day," which is modified by the preceding words. In this construction, "day" is the central noun. It is described by two modifiers. The first is "special," a standard adjective that qualifies the type of day. The second is "september 11th," a proper noun (a specific date) functioning as an adjectival modifier. It specifies precisely which "special day" is the subject, similar to how "brick" modifies "house" in the phrase "brick house." Therefore, the entire unit acts as a single noun in a sentence. ...