Changing sentences to pre tense

[danh]

Hi,

Need somehelp understanding this concept. I'm in a spanish class, trying to understand changing sentences to pre tense.

So in our exercises, the question is:
Paco va a Espana (n has a ~ on it, can't find the button on computer to make this happen) and we need to change this sentence to pretense. So, its a fill in the blanks type exercise, so the question is... Paco va a ___ a Espana la semana que viene. Then we are supposed to fill in the blank. Is the blank "ir"? I'm fairly sure it is, I just want to make sure.

One of the other sentences I'm having problems with is: Vas al concierto. And the question is:... Tu ___ a ir al concierto manana por la noche. I think the answer here is "vas" still. I'm not sure why ir comes after vas (my answer) in this fill in the blank though.

Has anyone got a good internet link I can read about this? or?

Thanks,

Daniel