"If I would have done something" vs "If I had done something"

Hi, everyone!
Let's talk about the conditional perfect.
When talking about something that didn't happen in the past, many English speakers use the conditional perfect (if I would have done) when they should be using the past perfect (if I had done).
For example, you find out that your brother saw a movie yesterday. You would have liked to see it too, but you hadn't known he was going. To express this, you can use an if - then clause. The correct way to say this is with the past perfect in the "if" clause, and the conditional perfect in the "then" clause:

If I had known you were going to the movies, [then] I would have gone too.

The conditional perfect can only go in the "then" clause - it is grammatically incorrect to use the conditional perfect in the "if" clause:

 If I would have known you were going to the movies, I would have gone too.

More examples:

If I had gotten paid, we could have traveled together.
If I would have gotten paid, we could have traveled together.

If you had asked me, I could have helped you.
If you would have asked me, I could have helped you.

The same mistake occurs with the verb "wish". You can't use the conditional perfect when wishing something had happened - you again need the past perfect.

I wish I had known.
I wish I would have known.

I wish you had told me.
I wish you would have told me.

We wish they had been honest.
We wish they would have been honest.

Hope you like this post!

Teacher Jô