-
There is a difference between these two ways of expressing the future. Generally "to be + going to" is used for actions that are going to happen very soon or to express a plan that you have. "Will" is used to express a promise, a prediction or something that you want to do in the future.
-
Future tense with "going to" is most commonly used in spoken language when one wants to refer to the immediate future, that is, something that is about to happen.
-
I’m going to learn English = voy a aprender inglés.
-
She is going to pay with a credit card = Ella va a pagar con una tarjeta de crédito (algo que está por ocurrir).
I am going to drop off my prescription over there = voy a dejar mi prescripción médica allá. -
"To be" + "going to" + verbo:
I am going to pay = yo voy a pagar.
You are going to pay = tú vas a pagar.
He is going to pay = él va a pagar. -
The future with "will" is used to talk about decisions made while talking:
-
I need to get my medicine. I will go to the pharmacy tonight.=Necesito comprar mi medicina. Iré a la farmacia esta noche.
I need some cash. I will pay with my debit card and ask for cash back.=Necesito algo de efectivo. Pagaré con mi tarjeta débito y pediré efectivo de vuelta. -
I’m sure it will rain tomorrow.= Estoy seguro de que va a llover mañana.
Gerardo Gómez will win the election.=Gerardo Gómez va a ganar las elecciones. -
I will pay later.
You will pay later.
He will pay later.
She will pay later.
It will pay later.
We will pay later.
You will pay later.
They will pay later. -
"Will" is a modal verb (or auxiliary) that is used to form the future. "Will" must always be accompanied by another verb to form the future.