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"Twice a day" is a phrase which is often translated as "dos veces al día", and "once" is an adverb which is often translated as "una vez". Learn more about the difference between "twice a day" and "once" below.
twice a day(
tways
 
uh
 
dey
)
A phrase is a group of words commonly used together (e.g., once upon a time).
phrase
a. dos veces al día
I take medicine twice a day.Tomo medicina dos veces al día.
b. dos veces por día
Do you shower twice a day?¿Te bañas dos veces por día?
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once(
wuhns
)
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
adverb
a. una vez
I go running only once a week.Salgo a correr solo una vez a la semana.
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.
b. en otro tiempo
This church was once a mosque.Esta iglesia fue en otro tiempo una mezquita.
a.
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
no direct 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.).
conjunction
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.
b. una vez
Once outside I felt better.Una vez fuera me sentí mejor.
A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).
noun
a.
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
no direct 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.
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