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"Si" is a form of "si", a conjunction which is often translated as "if". "Pero no puedo" is a phrase which is often translated as "but I can't". Learn more about the difference between "si" and "pero no puedo" 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).
pero no puedo(
peh
-
roh
noh
pweh
-
doh
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (general)
a. but I can't
Me gustaría ir al cine, pero no puedo: tengo que estudiar.I'd like to go to the movies, but I can't; I have to study.