vs
QUICK ANSWER
"Si" is a form of "si", a conjunction which is often translated as "if". "Cuando quieras" is a phrase which is often translated as "whenever you like". Learn more about the difference between "si" and "cuando quieras" 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).
cuando quieras(
kwahn
-
doh
kyeh
-
rahs
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (informal) (singular)
A word or phrase used to refer to the second person informal “tú” by their conjugation or implied context (e.g., How are you?).
a. whenever you like
Podemos irnos cuando quieras. Yo ya estoy lista.We can leave whenever you like. I'm ready.
b. whenever you want
Ya sabes que a esta casa puedes venir cuando quieras, y quedarte el tiempo que quieras.You know that you can come to this house whenever you want, and stay for as long as you like.
c. whenever you want to
Cuando quieras abrir la ventana, ábrela. No hace falta que nos pidas permiso cada vez.Whenever you want to open the window, just do it. There's no need for you to ask for permission each time.
