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"Si" is a form of "si", a conjunction which is often translated as "if". "Es verdad" is a phrase which is often translated as "it's true". Learn more about the difference between "si" and "es verdad" 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).
es verdad(
ehs
behr
-
dahd
)A phrase is a group of words commonly used together (e.g., once upon a time).
b. that's true
Este producto se vende bien - Es verdad, pero ha habido muchas devoluciones.This product sells well. - That's true, but there have been many returns.
c. that's right
Tu madre y yo estamos muy orgullosos de ti. - Es verdad, hijo.Your mother and I are very proud of you. - That's right, son.