September 11 2001
The keyword phrase "September 11, 2001" primarily functions as a proper noun. As a specific date, it names a unique point in time, much like a name identifies a specific person or place. This grammatical classification is foundational because it treats the date as a singular, identifiable entity, which is central to its historical significance. In addition to its role as a proper noun, the phrase is frequently used as an adjective, more specifically a noun adjunct. In this capacity, it modifies another noun to specify a direct connection to the events of that day. For example, in the phrase "the September 11, 2001 attacks," the date functions adjectivally to describe which attacks are being referenced. This dual functionality is key; when the date stands alone as the subject or object in a sentence (e.g., "The world was altered by September 11, 2001"), it is a noun. When it describes another noun (e.g., "the post-September 11, 2001 era"), it is an adjective. ...