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"Twice" is an adverb which is often translated as "dos veces", and "once" is an adverb which is often translated as "una vez". Learn more about the difference between "twice" and "once" below.
twice(
tways
)An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
1. (two times)
a. dos veces
He had to go to the store twice, because he forgot the milk the first time.Tuvo que ir a la tienda dos veces, porque se le olvidó la leche la primera vez.
once(
wuhns
)An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
2. (formerly)
a. antes
I once knew how to play the piano, but I've forgotten almost everything.Antes sabía tocar el piano, pero lo he olvidado casi todo.
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Once a liar, always a liar.El que miente una vez, siempre será mentiroso.
Once a teacher, always a teacher.Una vez que se es profesor, se es profesor para siempre.
A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
4. (when)
a. una vez que
He fell exhausted to the ground once he crossed the finish line.Cayó exhausto al suelo una vez que cruzó la meta.
A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
I decided to agree to it this once.Decidí permitirlo solo por esta vez.
I only saw him the once.Solo lo vi una vez.
