The keyword term is a noun phrase. The core grammatical subject, or head noun, is "celebrities." The preceding words function as modifiers that specify and narrow down this subject. This structure establishes that the main point of any article using this term is the people themselves, not the date or the concept of a birthday in isolation.
A detailed grammatical analysis breaks the phrase into its components. "Celebrities" is a plural noun, representing the primary topic. The word "birthday," also a noun, functions here as a noun adjunct (or attributive noun), modifying "celebrities" to describe the specific context. The term "sep 11," representing the date September 11th, acts as an adjectival phrase that further modifies the noun "birthday," specifying the exact date in question. The entire sequence narrows the focus from a general group (celebrities) to a highly specific subset.
In practical application for content creation, this grammatical structure dictates that the article's focus must be on the individuals who share this birthdate. The role of "celebrities" as the head noun means the article should provide information about these peopletheir careers, achievements, or life stories. The modifiers "sep 11" and "birthday" simply serve as the organizing principle or the criterion for including these specific individuals in the article. The content should, therefore, be a profile or a listicle about the people, not a general discussion of the date itself.
