Voy a estudiar — plans and intentions
Spanish builds "going to" exactly like English: ir (present) + a + infinitive. It is the everyday way to talk about plans and intentions.
Voy a estudiar esta noche. (I am going to study tonight.)
¿Vas a venir a la fiesta? (Are you going to come to the party?)
Vamos a comer fuera. (We are going to eat out.)
Three pieces, always in this order: ir + a + infinitive.
You already know these forms
| yo | voy a hablar | I am going to speak |
| tú | vas a hablar | you are going to speak |
| él / ella / usted | va a hablar | he / she is going to speak |
| nosotros | vamos a hablar | we are going to speak |
| vosotros | vais a hablar | you all are going to speak |
| ellos / ellas / ustedes | van a hablar | they are going to speak |
Only ir conjugates — the next verb stays in the infinitive
Voy a comprar pan. (I am going to buy bread.)
Ella va a ser médica. (She is going to be a doctor.)
Van a ver una película. (They are going to watch a film.)
Vamos a hacer una tarta. (We are going to make a cake.)
The infinitive can be any verb — regular or irregular, it makes no difference here.
Negative — no before ir:
No voy a salir esta noche. (I am not going to go out tonight.)
Mis padres no van a viajar este año. (My parents are not going to travel this year.)
Questions — just add question marks and intonation:
¿Qué vas a hacer este fin de semana? (What are you going to do this weekend?)
¿Vais a cenar en casa? (Are you all going to have dinner at home?)
ir a + infinitive vs futuro simple
Ir a + infinitive — plans and intentions already decided:
Este verano vamos a viajar a México. (This summer we are going to travel to Mexico.)
Also for what is clearly about to happen:
Mira el cielo: va a llover. (Look at the sky: it is going to rain.)
Futuro simple (hablaré) leans towards predictions and promises. In everyday speech, ir a + infinitivo is the most common way to talk about the future.
Time markers: esta noche, mañana, este fin de semana, el año que viene.
Traps for English speakers
Almost every error with this structure comes from dropping the a or changing the second verb.