* Adverb: When it modifies a verb, adjective, or another adverb, it acts as an adverb.
* Example: "I personally think the movie was excellent." (modifying the verb "think")
* Adjective: When it acts as a noun modifier, it functions as an adjective.
* Example: "This is my personal opinion." (modifying the noun "opinion")
Let me know if you have a specific sentence in mind and I can help you identify the part of speech!