vs
QUICK ANSWER
"Si" is a form of "si", a conjunction which is often translated as "if". "Porque no" is a phrase which is often translated as "just because". Learn more about the difference between "si" and "porque no" below.
si(
see
)A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
porque no(
pohr
-
keh
noh
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. just because
¿Por qué no quieres ir a su fiesta? - Porque no.Why won't you go to her party? - Just because.
b. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
No me vengas con excusas. No hiciste la tarea porque no te dio la gana.Don't come to me with excuses. You didn't do your homework just because you didn't feel like it.
No hice la compra porque no tuve tiempo.I didn't do the shopping because I didn't have time.
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Rezo porque no llueva mañana y se suspenda el partido.I pray that tomorrow doesn't rain and the match isn't cancelled.
Hicieron lo que pudieron porque no me sintiera solo.They did all they could so that I didn't feel lonely.
