When we want to talk about things that are not true and not happening in our lives, or about something that we want to happen in the future, we can use the phrases «I wish/If only». We can also use them to talk about something that already happened (or didn’t happen) in the past and how we want for these things to be different.
To talk about wishes for present/future: «I wish/If only + past tense»
I wish I had a car.
If only I had more money — I could go to my best friend’s wedding in London!
I wish I didn’t have to work so much.
If only I didn’t need to drive so much every day.
To talk about past regrets: «I wish/If only + past perfect»
I wish I had studied more languages when I was younger.
If only I hadn’t invested all my money in this project!
I wish I hadn’t said no to that job in Moscow.
If only I had known Bitcoin would be so successful!