Dear Miriam,
Yes. You are totally right at the very begining of your previous post. Any variants of one sentence will be annoying enough to send me to a mental house. The listings on Google are considered as for reference only. One should never buy all the the stories without any doubt in mind.
It is not difficult for native speakers to explain the meaning. Maybe some of them are not well equipped with grammatical rules to teach, but almost all of them can teach how to differentiate between meanings, for example, my wish/hope examples. They know what sounds odd and what doesn't. For us, ESL/EFL learners, it seems to take forever to get there, you know
Being a ESL/EFL teacher, I have to be nit-picky at learning your language. I will never know whether or not my students will bring up any possible questions which I am not able to control or offer them the best explanation. What's worse, some students learn English in a jumping way, they are too anxious to learn. Eventually, they mess up everything. All I can do is provide them with rules as simple as possible. For example,
Wish
1. used to express good wishes, followed by nouns. ==> Wish you a good day.
2. used to express something unreal, impossible or unlikely happened in the future.
==> I wish I could fly.
==> I wish you have a good day. (I saw this sentence in a textbook used to teach junior high school student, secondary education.) I would think it contradictable. How can you wish someone has a nice day unless you really wish so.
See, any slight change in the sentence would kill the curious cat like me. I slept at 4am last night just because one of my class asked me to teach them 'Participle.' I had my nose buried in 5 grammar books, trying to figure out the simplest way to present the most complicated concept. My lecture is just fine for them, they grasp the main idea easily. Haha, you must have thought I was a serious person. Most of the time, I'll play with English happily. But I'm serious here and I need an nice explanation.
Regarding your last paragraph, I must say you are a 5-thumb up teacher. It's honorable to be one of your student here. And I'm so sorry that my posts make your head spinning, and I feel guilty here after reading your excellent posts, because my walking on air makes you suffer in the hell. haha.