"I wish I went" or "I wish I had gone"

Question

In the following sentences, there is probably an aspectual error.

Wouldn't that error rather be in:

'I wish I went to the party, which I had been invited to last week.'

than

'I wish I had gone to the party, which I had been invited to last week.'

?

For me, "I wish I had gone..." absolutely fits in, making the order of events perfectly correct and suitable.

Note: The only reason I have made this OP is because my professor, who is NOT a native English speaker, claims the opposite. He probably mistook subjunctive [mood] meaning for the literal meaning of the past.

Answer 1

Those are conditional sentences. The first one is not correct. It’s the second conditional sentence kind, which means that the use of ‘wish’ and a simple past verb expresses a desire that could come true in the future.

The second sentence is the third conditional sentence kind, it’s constructed using ‘wish’+ ‘had’/‘had not’ + past participle verb, and expresses regrets or past wishes.

It’s common for people to use them the wrong way.

Answer 2

For describes wishes about the past we usually use past perfect tense:

I wish I had brought my wallet.

And, when we need to talk about two past situations mutually related and clarify their chronology, we should use present perfect + past perfect:

They had called before it has happened.

However, your sentence don't actually treat about witch situation occurred first (although by context we are able to identify it). This way, the simple past is more natural and appropriate for the second phrase. Resulting at:

I wish I had gone to the party, which I was invited to last week.

The same way, there's no problem for use past perfect in the second sentence as well. Thus, your first alternative is not correct, but the following one is right.

I wish I had gone to the party, which I had been invited to last week.