Form
I wish / If only + S + Past Simple.
I wish I had more free time.
If only we knew what to do.
Meanings
Wishes about the Present or Future
We use I wish + Past Simple to express a desire for a present or future situation to be different. The situation is unreal.
I wish I was taller.
(Reality: I am not tall, but I want to be.)
I wish I didn’t have to work tomorrow.
(Reality: I have to work tomorrow, but I don’t want to.)