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"Yo" is a pronoun which is often translated as "I", and "nunca" is an adverb which is often translated as "never". Learn more about the difference between "yo" and "nunca" below.
yo()
A pronoun is a word that stands in for a noun (e.g., she).
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
3. (psychology)
nunca()
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
1. (not ever)
b. ever (after "not")
Nunca llegas a tiempo.You don't ever arrive on time.
¿Vives en México y nunca has comido tacos?You live in Mexico and you haven't ever eaten tacos?