Here's why:
* It modifies verbs, adjectives, or other adverbs. It tells us *how* something is done or to what degree something is true.
* Example: "He walked comparatively slowly." (modifies the verb "walked")
* Example: "This house is comparatively expensive." (modifies the adjective "expensive")
* Example: "She spoke comparatively quietly." (modifies the adverb "quietly")
* It doesn't function as a noun, pronoun, adjective, verb, preposition, conjunction, or interjection.
Let me know if you have any other words you'd like to analyze!