Bakasi, to judge by your own writing, I would say that you understand English rules far better than do many native speakers of the language. You are not giving yourself enough credit.
Thanks for the praise, Lynn. I think I've nailed most of the grammar rules, but the commas still remain a mystery to me. Terry, who betaed two long stories for me, probably thought that I simply put my commas into a box, shook them and scattered them across my text randomly. He was mildly appeased when I mentioned the German comma rules.
I tried reading the concise word on commas, but had to stop after rule three.
I don't think that I ever learned English comma rules in school. There are some different rules with speech tags, too, which regularly have me reeling.
So, your Gremlins certainly have a field day with me.
But I'm still trying to improve and I think that at least one comma rule has made it into my thick head.