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"Cuándo" is a form of "cuándo", an adverb which is often translated as "when". "Por qué" is a form of "por qué", a phrase which is often translated as "why". Learn more about the difference between "cuándo" and "por qué" below.
cuándo(
kwahn
-
doh
)
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
adverb
a. when
¿Cuándo vas a terminar tus deberes?When are you going to finish your homework?
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
masculine noun
a. when
Nos vamos a casar, pero el cuándo y el dónde aún no lo sé.We are getting married, but I don't know when or where yet.
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por qué(
pohr
 
keh
)
A phrase is a group of words commonly used together (e.g., once upon a time).
phrase
a. why (adverb)
¿Por qué no te gustan las guayabas?Why don't you like guavas?
a. why (adverb)
Me gustaría saber por qué los gatos ronronean.I would like to know why cats purr.
a. what (pronoun)
¡Por qué cascadas más hermosas pasó la lancha!What beautiful waterfalls the skiff passed through!
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
masculine noun
a. reason
No tenían por qué sospechar que yo era un espía.They had no reason to suspect I was a spy.
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