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"Acabar de" is a transitive verb phrase which is often translated as "just", and "adverbio" is a noun which is often translated as "adverb". Learn more about the difference between "acabar de" and "adverbio" below.
acabar de()
A transitive verb phrase is a phrase that combines a verb with a preposition or other particle and requires a direct object (e.g., take out the trash.).
el adverbio()
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).