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"Si" is a form of "si", a conjunction which is often translated as "if". "Muy bien" is an interjection which is often translated as "very good". Learn more about the difference between "muy bien" and "si" below.
muy bien(
mwee
byehn
)An interjection is a short utterance that expresses emotion, hesitation, or protest (e.g., Wow!).
A phrase is a group of words commonly used together (e.g., once upon a time).
a. alright then
Ya empieza a oscurecer, así que me voy a casa. - Muy bien. Nos vemos mañana.It's getting dark already, so I'm off home. - Alright then. I'll see you tomorrow.
b. very well (old-fashioned)
A word or phrase that is seldom used in contemporary language and is recognized as being from another decade, (e.g., cat, groovy).
No nos queda tiempo hoy. - Muy bien; lo dejamos para mañana.We don't have enough time left today. - Very well; we'll leave it for tomorrow.
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).