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"Si" is a form of "si", a conjunction which is often translated as "if". "Tu" is a form of "tu", an adjective which is often translated as "your". Learn more about the difference between "si" and "tu" 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).
tu(
too
)An adjective is a word that describes a noun (e.g., the big dog).
1. (informal) (possessive)
A word or phrase used to refer to the second person informal “tú” by their conjugation or implied context (e.g., How are you?).