I WISH

For a wish about a present situation that you would like to be different:

I WISH + PAST SIMPLE

• I wish I had more money.
• I wish I could fly.
• If only I was/were taller.

For a regret about a past situation (things you can't change now):

I WISH + PAST PERFECT

• I wish I had studied more.
• If only I hadn't eaten that.
• I wish I had arrived on time.

We use I wish + would to complain about a situation or someone's annoying habit that we want to change:

I WISH + WOULD + VERB

• I wish you would stop smoking.
• I wish it would stop raining.
• I wish he would listen to me.

Note: We don't usually use "I wish I would..." because we can change our own behavior!