USE TO BE GOING TO
This periphrasis refers to the use of tense: idiomatic FUTURE.Corresponding to the idiomatic way of expressing actions that will occur in the near future.This tense is used:
 

1.-When referring to the future, probable and inevitable.

2.-To highlight an action in the future and when you have already taken the decision to do something in particular.
 

The future idiomatic formed with the auxiliary verb "to be" combining (am, is, are) more

how "going to" in Spanish maps to "will" a verb more simply, but he may complement sentence. Structural model:

I am going to study         -voy a estudiar

You are going to study     -vas a estudiar

He

She   is going to study          -va a estudiar

It

We are going to study     -vamos a estudiar

You are going to study     -van a estudiar

They are going to study     -van a estudiar

 

How "going to" expresses the subject's intention to run some future action.
 
Intend to use this kind of sentences is always deliberate and usually also gives the idea that some preparation for action has already been made.
 
This time is divided into three grammatical modes according as shown:

 

ESTRUCTURA GRAMATICAL DEL FUTURO IDIOMÁTICO

 

FORMA AFIRMATIVA

 

PRONOMBRE / NOMBRE / SUSTANTIVO + PRESENTE TO BE + GOING TO + VERBO PRESENTE + COMPLEMENTO

 

EJEMPLO :

 

I am going to teach english language in bachelor´s college

Voy a enseñar el idioma inglés en el colegio de bachilleres

 

FORMA NEGATIVA

 

PRONOMBRE / NOMBRE / SUSTANTIVO + PRESENTE TO BE + NOT + GOING TO + VERBO PRESENTE + COMPLEMENTO

 

EJEMPLO:

 

I´m not going to teach english in bachelor´s college

No voy a enseñar ingles en el colegio de bachilleres

 

FORMA INTERROGATIVA

 

PRESENTE ( TO BE ) + PRONOMBRE / NOMBRE / SUSTANTIVO + GOING TO + VERBO PRESENTE + COMPLEMENTO + ?
 

EJEMPLO:
 

Am i going teach english in bachelor´s college ?

¿ voy a dar clases en el colegio de bachilleres ?

¿ voy a enseñar inglés en el colegio de bachilleres ?