I regret not studying harder when i was at school. (Studied)
If only _______ when i was at school.

I want the neighbours to stop making so much noice. (make)
I wish the neighbours _______ noise.

What a pity that they cancelled the match! (called)
If only they _______ match.

I'm sorry you didn't meet my brother. (wish)
I ______ my brother.

It's a pity I can't cook well. (better)
I wish I ______ cook.