Be Going To

1. Use of the going to-future

1.1. planned actions in the future

We are going to sing at the party.

1.2. You are certain that sth. is going to happen in the future.

Look at that car! It is going to crash into the yellow one.

2. Signal words

no unambiguous ones

3. Form

to be (am, are, is) + going to + infinitive

4. Examples

4.1. Affirmative sentences in the going to-future

Long forms	Contracted forms
I am going to play handball.	I'm going to play handball.
You are going to play handball.	You're going to play handball.

4.2. Negative sentences in the going to-future

Long forms	Contracted forms
I am not going to play handball.	I'm not going to play handball.
You are not going to play handball.	You're not going to play handball.
	You aren't going to play handball.

4.3. Questions in the going to-future

Long forms	Contracted forms
Am I going to play handball?	not possible
Are you going to play handball?

ATTENTION!!

Do not mix up with the Present Progressive!

going to-future	Present Progressive
He's going to read the book.	He's reading the book.

Taken from: http://www.englisch-hilfen.de/en/grammar/going_to.htm