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"Si" is a form of "si", a conjunction which is often translated as "if". "Hay" is a form of "hay", an impersonal verb which is often translated as "there is". Learn more about the difference between "si" and "hay" 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).
hay(
ay
)An impersonal verb is a verb with no apparent subject (e.g., Llueve en España.).
a. there is (singular)
A word or phrase that is singular (e.g., el gato).
Hay un problema con el nuevo modelo del celular.There is a problem with the new model of the cell phone.
a. is there (singular)
A word or phrase that is singular (e.g., el gato).
¿Hay un parque por aquí?Is there a park around here?