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"Estoy" is a form of "estoy", a phrase which is often translated as "I'm". "Si" is a form of "si", a conjunction which is often translated as "if". Learn more about the difference between "estoy" and "si" below.
estoy
A phrase is a group of words commonly used together (e.g., once upon a time).
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).
