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"Si" is a form of "si", a conjunction which is often translated as "if". "Ahora" is an adverb which is often translated as "now". Learn more about the difference between "si" and "ahora" below.
si()
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).
ahora()
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
2. (very soon)