to be going to + V1 is a special construction. We use it to talk about plans and predictions (when we have evidence). will + V1 is the Future Simple and is usually used for spontaneous decisions (but also some kinds of predictions). Choose the correct answer. (If this seems complicated - the main idea is that for plans it is "going to" construction).

We are going to go to the beach tomorrow.

It's cold in here. I'll (I will) open the window.

Look at the sky. I think it is going to rain soon.

If you eat all those cakes you are going to be sick.

Jane is going to study Maths at University.

You could ask Jim, but he won't do it. (will not). He is lazy.

Are you going to fly or take the train Peter?

She isn't going to walk to work. She is going to take the train.

Look at James running for the train. Will he make it in time, I wonder?

We are going to have lunch and then visit the museum.