Future with Be Going To

Use--> plans, intentions, decisions

Afirmative

Subject + to be + going to + infinitive

EX: I am going to come to school tomorrow

Negative

Subject + to be + not + going to + infinitive

EX: I'm not going to school tomorrow

Interrogative

to be + subject + going to + infinitive

EX: Am I going to come to school.

Time expressions

I've decided
I've planned

Future with Will

Use--> predictions, promises, voluntary action

Afirmative

Subject + will + infinitive

EX: I will dance

Negative

Subject + won't + infinitive

EX: I won't dance

Interrogative

Will + subject + infinitive

EX: Will I dance?

Time expressions

I'm sure
maybe
perhaps