I'm a native English speaker who, a lifetime ago, moved to Shanghai to teach English to adults. One of my biggest struggles when I first started was explaining to students not just what the correct English should be in a given situation, but why that was the correct English. This had a profound effect on my view of expertise and experts in general.
As someone that speaks English as my second language, the trick of English is to memorize all the exceptions and then accept that the English spelling is just made up to mess with foreigners.
Looking at you, the "b" in debt, that I was pronouncing for a long time growing up and learning a lot of words from reading.
A big one is also "ed" like "jogged". It looks like jog ged, so surely it's pronounced that way. Bahaha, no - gotcha! It's jogd! But we like extra letters and there must be vowels even when completely and absolutely unpronounced. Not sure if this is better or worse than Russian which seems to have no problem with squeezing a half dozen consonants side by side and saying, 'good luck.'
Honestly English spelling is the worst at least of Western Europe. Its so bad it that unless you know some IPA and learn the words pronunciation one by one youre misunderstood all the time. Its also imposible to guess with 100% accuracy how a word is said unless being told.
Schwas everywhere randomly (why is it adjust (uhd 'juhst) and not ad 'juhst when we have accept (ak 'sept). In German this is way more consistent.
Diphthongs everywhere, almost no pure monophthongs. Which is a language feature but in written form is also fucked. I tend to have problems with oh vs aa sounds. E.g. poland is pou luhnd and polish is paa lish.
Stress isnt written.
Consonants not only can be spelled differently but also said differently. Gif vs djif, cell vs celt, china vs machine
This makes the language way harder in a high level than it should be if it had had some spelling reform at some point.
Sorry for not using IPA Im on the phone.
There's two pronunciations of 'polish' though: the one you mentioned being what one does to grandmother's candlesticks, and 'pou lish' referring to someone or something from 'pou luhnd'.
As an ESL speaker living among native speakers, my take: No human language has "the correct [expression]". What is best suited is the thing that's often used, or an interesting but understandable twist on it that will be familiar to the audience, and grammar should be viewed as descriptive not prescriptive. Grammar is just some OCD person's attempt to write down a simplification of reality, nothing more.
The best way to learn written English is by reading English books[1]; the best way to learn spoken English is to interact with native speakers, a lot. Build familiarity without ever trying to justify "why that was the correct [expression]". It'll just feel right when it's right, because it fits the statistical pattern your brain has picked up.
Grammar is to language like ballistics is to throwing & catching a ball.
[1]: For someone with a basic grasp of the language but not enough exposure yet, Young Adult content is often easiest to read. I read most of the Sherlock Holmes stories, some James Bond novels, and a lot of Heinlein growing up.
One of the big takeaways was not to over-value the knowledge I had gained learning English via immersion in an English-speaking culture, and conversely not to under-value that of the local teachers, who had gained their knowledge in the classroom. It's a cliche at this point to say that "street smarts > book smarts", at least in my culture. My teaching job taught me that there are situations where neither type of knowledge by itself is sufficient, and that both types have their place.
For example, as I mentioned I frequently ran into situations where I could tell whether a student's sentences were correct or not, but I struggled to explain why. One example from early in my teaching career was when students would place their adjectives out-of-order, for example "The German, red, old, large car..." instead of "The large, old, red, German car...". I intuitively knew that the former is incorrect and the latter is correct, but when students would ask me why, I struggled to articulate a reason.
But the local teachers on staff (i.e. native Chinese speakers) would chime in with "The order of adjectives in English is opinion, size, age, shape, color, origin, material, and purpose." They (the local teachers) still made mistakes in their English, but they had mostly memorized the rules from classroom study, and could recite them better than I could. Which was helpful to both us as native speakers (who wanted to give the students concrete answers to their questions) and to the students (who wanted rules to govern future scenarios they might encounter).
I was admittedly a bit cocky coming into that job, thinking I was qualified simply because I was a native speaker. I quickly learned that teaching a subject is a skill unto itself. It requires abilities like gauging levels of understanding by asking comprehension questions, and tailoring the subject matter to those comprehension levels, so as not to either talk down to the student or talk over their head.