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"Sí" is a form of "sí", an adverb which is often translated as "yes". "Cómo no" is a phrase which is often translated as "of course". Learn more about the difference between "cómo no" and "sí" below.
cómo no(
koh
-
moh
noh
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
¿Cómo no han llamado para decir que llegaban tan tarde?How come you didn't call to say you'd be arriving so late?
Conduciendo así, no sé cómo no tiene un accidente.The way he drives, I don't know how he doesn't have an accident.
3. (colloquial) (used to express disbelief)
A word or phrase that is commonly used in conversational speech (e.g., skinny, grandma).
a. right (colloquial)
A word or phrase that is commonly used in conversational speech (e.g., skinny, grandma).
¿Así que tú eres el campeón mundial de karate? Claro, cómo no.So you are the karate world champion? Yeah, right.
sí(
see
)An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
a. yes
¿Quieres ir al cine? - Sí, pero primero hay que comer.Do you want to go to the movies? - Yes, but let's eat first.
2. (emphatic)
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Yo sí quiero acompañarlos a Disney.I do want to go with you to Disney World.
Ella no aprobó, pero yo sí.She didn't pass, but I did.
An interjection is a short utterance that expresses emotion, hesitation, or protest (e.g., Wow!).
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
A pronoun is a word that stands in for a noun (e.g., she).
a. himself (third person singular masculine)
Suele jugar ajedrez con sí mismo.He usually plays chess against himself.
b. herself (third person singular feminine)
¡Se envió una carta a sí misma!She sent a letter to herself!
c. itself (third person singular)
El hilo se está enredando en sí.The string is getting tangled up in itself.
e. yourself (second person singular formal)
Solo desea el bien para sí.You only wish good for yourself.
f. yourselves (second person plural formal)
¡Solo tienen que creer en sí mismos!You just have to believe in yourselves!