Future in the Past is sometimes described as 'the future seen from the past'. But it's really more like 'the future seen from the past which is in turn seen from now':
- Somebody thinks about the future:
- I will be meeting her later on. - Sometime later we look back at him thinking about the future:
- He knew he would be meeting her later on. - I think about the future:
- I'm going to buy a new computer today - The next day I remember:
I was going to buy a computer yesterday, but then I realised I couldn't afford it. - The newspapers announce something that's going to happen:
- There is to be a tax cut. - Sometime later I remember reading about it:
- I read that there was to be a tax cut.
That's just about the the basis of it. Learn more by doing these exercises, and at the same time brush up your knowledge of future forms, future expressions with the verb to be and future time clauses.