Here's why:
* It modifies a verb, adjective, or another adverb: It tells us *how* something is done or experienced. For example:
* "He spoke negatively about the project." (modifies the verb "spoke")
* "She had a negatively skewed opinion." (modifies the adjective "skewed")
* "The car was driving negatively fast." (modifies the adverb "fast")
* It ends in "-ly": Many adverbs in English end in "-ly".
Let me know if you have other words you'd like help identifying!