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"Si" is a form of "si", a conjunction which is often translated as "if". "Con que" is a preposition which is often translated as "as long as". Learn more about the difference between "si" and "con que" 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).
con que(
kohn
keh
)A preposition is a word that indicates the relationship between a noun and another word (e.g., He ran through the door.).
a. as long as
Me contento con que arregles tu habitación.I am satisfied as long as you tidy up your room.
a. with which
La policía no ha encontrado todavía el arma con que dispararon a la víctima.The police haven't yet found the weapon with which the victim was shot.