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"Si" is a form of "si", a conjunction which is often translated as "if". "Qué bien" is an interjection which is often translated as "that's great". Learn more about the difference between "si" and "qué bien" 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).
qué bien(
keh
byehn
)An interjection is a short utterance that expresses emotion, hesitation, or protest (e.g., Wow!).
a. that's great
Conseguimos la casa que queríamos. - ¡Qué bien!We got the house we wanted. - That's great!
b. that's good
Vamos a pasar Semana Santa con mi familia en Querétaro. - ¡Qué bien!We're going to spend Easter vacation with my family in Queretaro. - That's good!
A phrase is a group of words commonly used together (e.g., once upon a time).