vs
QUICK ANSWER
"Si" is a form of "si", a conjunction which is often translated as "if". "Voy a comprar" is a phrase which is often translated as "I'm going to buy". Learn more about the difference between "voy a comprar" and "si" below.
voy a comprar(
boy
ah
kohm
-
prahr
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. I'm going to buy
En cuanto ahorre dinero suficiente para una entrada, voy a comprar una casa.I'm going to buy a house as soon as I've saved enough money for a deposit.
a. I'm going to do the shopping
Voy a comprar. ¿Necesitas algo del supermercado?I'm going to do the shopping. Do you need anything from the supermarket?
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).
