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"That happened" is a phrase which is often translated as "eso sucedió", and "once" is an adverb which is often translated as "una vez". Learn more about the difference between "that happened" and "once" below.
that happened(
thaht
 
hah
-
pihnd
)
A phrase is a group of words commonly used together (e.g., once upon a time).
phrase
a. eso sucedió
I don't know when that happened.No sé cuándo eso sucedió.
b. eso ocurrió
Do remember when the church burned down? - I do. That happened a long time ago.¿Te acuerdas de cuando se incendió la iglesia? - Sí. Eso ocurrió hace mucho tiempo.
c. eso pasó
The meat came out really tough. - That happened because you didn't reduce the heat.La carne salió muy dura. - Eso pasó porque no redujiste el fuego.
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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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