1. You want to study Law in Italian but you don't speak Italian.
I wish I knew how to speak Italian, I would study Law in Italian.
2. You wanted to surprise your family with a nice dinner, but you overcooked the chicken.
I wish I hadn't overcooked the chicken, I would have surprised my family with a nice dinner.
3. You wanted to take dance classes, but you didn't sign up for the class on time.
I wish I had signed up for the dance class on time, I would have taken dance classes.
4. You wanted to go on holiday this year, but you didn't save enough money.
I wish I had saved enough money, I would have gone on holiday this year.
5. You can't go up the Eiffel Tower because you are afraid of heights.
I wish I weren't afraid of heights, I would go up the Eiffel Tower.
6. You want to see a movie, but you have no one to go with.
I wish I had someone to go with, I would see a movie.