watashi wa kare no tanjoubi wo wasuremashita = I forgot his birthday
could be more idiomatically rendered:
watashi wa kare no tanjoubi wo wasuremashite shimaimashita
The translation for the second sentence is the same as the first, but now with a sense of regret! There's no simple way of conveying this in standard English, without adding a word such as "alas" or "regretfully", which seems a bit clunky. However, it occurs to me that you can get much the same effect in some southern US dialects by use of the word "done", as in: "I done forgot his birthday".
Non-standard English is also helpful sometimes with pronunciation. Japanese has many words that are rendered in romaji with a double consonant (signalled in hiragana with っ). Hence for example:
shippai = しっぱい = 失敗 = failure
In English double consonants typically affect the pronunciation of preceding vowels rather than the consonants themselves ("hopping" vs "hoping"), but in Japanese a double consonant is marked with a small pause, which I've seen described as quite a tricky thing for foreigners to master because it has no equivalent in standard English pronunciation. It does, however, have an equivalent in Yorkshire dialect, in phrases such as "There's trouble down t'mill." So, when I was learning this bit of Japanese I just channelled Geoffrey Boycott. Very useful.
Anyway, that last example was just a digression. What I really wanted to ask was, what other shades of meaning are available through the pronunciation or grammar of non-standard varieties of English, that aren't available through standard ones?
Note, I'm not asking for items of vocabulary, fascinating as they are: obviously there are whole dictionaries full of terms for the kind of mist you only see off Bamburgh when there's an 'r' in the month. I'm specifically after elements of grammar or pronunciation that carry meaning.
One more example. Standard English doesn't have a plural second person, whereas lots of non-standard Englishes do, from "You all" to "Yous" (sp?). Obviously the non-standard Englishes are here conveying shades of meaning not available to the standard variety.
I'm sure there must be many other examples of the same kind. But what are they?