Will /going to/現在進行式

All the three can be used for something that will happen in the future.

We use 'will' for something that will probably happen.
Example: The 2008 Olympic Games will be successful.

We use 'going to' for something that is decided to be done in the future.
Example: I am going to visit Beijing during the 2008 Olympic Games.

We use present continuous tense for what someone has arranged to do in the future.
Example: I will be visiting Beijing during the 2008 Olympic Games. I have already booked the tickets.

現在進行式:running,flying.....