Past Perfect or Past Simple? Or both?
From Collins Cobuild entry "should":
3) MODAL If you say that something should have happened, you mean that it did not happen, but that you wish it had.
I fully understand the general meaning of the explanation, but am a bit puzzled by tenses in this sentence. What is wrong with the following variants and in the case they happened to be correct, what would be a difference in meanings of both comparatively to the COBUILD variant?
- If you say that something should have happened, you mean that it had not happened, but that you wish it had.
- If you say that something should have happened, you mean that it did not happen, but that you wish it did.