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"Si" is a form of "si", a conjunction which is often translated as "if". "Que si" is a phrase which is often translated as "that if". Learn more about the difference between "si" and "que si" below.
si(
see
)
A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
conjunction
a. if
Si llueve mañana, cancelaremos el pícnic.If it rains tomorrow, we will cancel the picnic.
a. whether
Preguntó si me estaba divirtiendo.He asked whether I was enjoying myself.
b. if
Paco quiere saber si Laura también va a asistir.Paco wants to know if Laura is also going to attend.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
masculine noun
a. B
Primero lo oí en si menor.I first heard it played in B minor.
b. ti (solfége)
Practiquemos las escalas en orden inverso: do, si, la...Let's practice scales in reverse order: do, ti, la...
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que si(
keh
 
see
)
A phrase is a group of words commonly used together (e.g., once upon a time).
phrase
a. that if
Recuerda que si llueve, el paseo se suspende.Remember that if it rains, the field trip will be cancelled.
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