adverb: Gram. Accident that, for the sense of the sentence or the meaning of the word, does that a noun transform in verb, adjective, or another adverb or vice versa; examples: human - human; in this sentence the verb be in his infinitive mode, has suffered an accident that transforms it into a noun, and therefore the word "Be " and the word " be " they are adverbs. There are adjectives that turn nouns, and vice versa, for example: José Blanco is white, and we see that a surname is transformed into an adjective. Some adverbs are transformed into another different adverb, for example, the demonstrative pronouns are adverbs when personal pronouns, and in this case they are marks an accent or tilde it: that's me! I am he...!