vs
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"Si" is a form of "si", a conjunction which is often translated as "if". "Yo lo sé" is a phrase which is often translated as "I know". Learn more about the difference between "si" and "yo lo sé" 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).
yo lo sé(
yoh
loh
seh
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (general)
a. I know
Va a deprimirse mucho cuando sepa la noticia. - Yo lo sé, lo sé, pero no puedo hacer nada.She'll be very depressed when she hears the news. - I know, I know, but there's little I can do.
b. I know it
Yo lo sé desde las Navidades, pero aún no he querido decirle nada a mi familia.I know it since Christmas, but I didn't want to tell my family yet.
