The correct answer is, ir de pesca.
When people go fishing, that is called ir de pesca.
If the starting tense is future and in the ellos form and its a regular verb the answer would be comprarían.
Me: I need a later curfew I have so much things to do and don't have time to do what I want (have fun)
Mom: no you need to go to bed early so you can do what you need not what you want.
Me: ok ima make you happy for now but if you don't let me now I'm going to later this will cause experiences that I have never encountered later in life that I could know about sooner but couldn't because i was restricted and when I have less common sense then everyone when I'm older it's your fault.
