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"Si" is a form of "si", a conjunction which is often translated as "if". "Uno" is a form of "uno", an adjective which is often translated as "one". Learn more about the difference between "si" and "uno" 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).
uno(
oo
-
noh
)An adjective is a word that describes a noun (e.g., the big dog).
a. one
Me queda solo un dulce.I've only got one candy left.
Necesitamos una moneda más para completar el conjunto.We need one more coin to complete the set.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
A pronoun is a word that stands in for a noun (e.g., she).