Re: how to fix the bug of dc4
It mixes Don McLeans "American Pie" for the music with the story from Star Wars - Episode 1 - "The Phantom Menace", yes.
The trouble is, there are so many forms of "slang", and that's the main area for deviation in "global" English. Slang terms are colloquial, and based in regional and Ethnic heritage.
For example, both Cockney (from the greater London area) and Australia use a form of "Rhyming Slang" which requires one to know the common phrase who's end sounds like the word you are mimicking. But the rhymes are different in the to sub-dialects. "Apples and Pears" (Apples) = "Stairs", "Syrup of Figs" (Syrups) = "Wigs", "Tit for Tat" (Titfer) = "Hat", "Ruby Murry" (Ruby) = Curry etc. I don't know the Australian variant very well.
In Britain, "Cockney slang" is often intermixed with
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, which was developed by the homosexual community when homosexuality (among men) was a crime punishable by death, (from the Victorian reign right up until the mid 60s) in order to escape that cruel justice. But that "slang" has also evolved. So the original meaning of "naff" ("Not Available For Ducking" a straight man) is now anything that is not very good. The popular 4 letter word "duck" is also an Acronym from the time of the Norman conquest of the English, where prostitution (previously an honourable trade profession) became a crime, and practitioners where sentenced "For Unlawful Carnal Knowledge".
There is "Hip Talk", which was a slang first developed in the late 50s' and early 60s' by "beatniks" and associated with "Hippies" and the "Surfing" / "New Age" and "Travelling" communities is another common example. "Far out" = "an incredible thing", "No way" = "Extraordinary", "Bummer" = "That's sad", "Bodacious" = "A daring and rightfully achievement" etc.
There is the reverse psychology of African American "Street Slang" (that I'm very bad at) where "Bad" = "Good", "wigger" = "Friend", "Honkey" = "White man", "Brother" = "Black man", "Slaughtered" = "Well appreciated" etc.
And then you get the typical Jamaican "Street Slang" that... IDK. If you watch this, you will get a very good example, and very few "English" speakers understand this form of "slang":-
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I can tell you that "Word" = "Tell me" or "I'm telling you", "Boom boom down" = "Assassination", "Play" = "Trick", "Jiggle it rait" = "Shapely woman", "Lick up" = "Beat up", "Flame" = "lover" etc.
There is traditional Jamaican slang in there too so "Likki" is "small" ("little"), "babylon" = "the authorities" (traditionally, white men), "most high" / "jah" = "God" (Jah Rastafari), "busted" = "caught out" / "a failed prank" / "arrested", "Lone-taim gwan" = "in the past", "riet naow" = "Okay" or "in the present", "me" = "I", "him" = "he", "her" = "she", "Ya" = "you", "ya naow" = "you understand" ("you know?"), "tinke" = "work it out" or "estimate" ("think" different connotation), "dyam fool" = "careless" ("Damned fool" different connotation) etc.
Something more like this:-
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The video you posted uses many slang dialects, including old sailing slang from the "Pirates of the Caribbean" so "Swarthy dog" = "good colleague", "slip sway" = "set sail", "salty sea urchin" = "one for who the ocean has long been his home", "scallawag" = "thief" / "wrong doer" etc. It's mostly a collection of old English, and early English colonial colloquialisms.
You get "slang" from Jewish migrants producing a complete new language "Yiddish" as a mix of traditional "Hebrew" and the many languages they encountered in their travels, and "Yiddish" finds it's way into the languages of all the places they visit(ed), so "shister" comes from the German for "defecation" but means "bad person" in Yiddish slang, hence we also call bad people "shits".
Then you get the "Dance culture" slang where "poop" is a mind altering chemical substance (usually of dubious legality), "wicked" = "a good time", "tearing it up" = "really working hard and having fun", (extreme version of the 1940 dance term "cut a rug", where high heels would trash carpet) "blaze" = "smoking pot" etc.
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The street slang from second or third generation Indian and Pakistani immigrants (who's fore-fathers where probably escaping the turmoil of the exit of the British Empire and splitting of India and Pakistan) here in Britain is very popular, and you see it a lot in "Goodness Gracious Me", where "init" is abbreviated from "isn't it" but means "Don't you think?" or "You know what I'm talking about." and such.
Much of which comes from the "Ragga" influence from the joining of the Caribbean and Asian (Indian / Pakistani) immigrants.
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So... all in all, you have to work out the heritage of the "slang" you are listening to, in order to work out what the words, or phrases mean. Out of context, they are pretty meaningless. And this is where a lot of people trip up using automatic translators, in any language. I know there is a lot of "Brazilian slang" used on MIB which doesn't translate, because it isn't common / traditional "Portuguese", and sadly many Brazilians aren't aware of the differences between their contemporary mode of speech (their cultural identity) in comparison to the Portuguese they inherited (or had forced upon them) from their colonial fore-bares.
I suspect you (unlike many other Brazilians) would know far more about that. And certainly more than I do.
The history of colonisation is something which Britain understands well... negatively, from our former British Empire, starting with the reign of Queen Elizabeth I. But also from the waves of Northern European and Mediterranean colonisation of the British Isles which forged the "English" language in the first place.
"English" has always been a "melting pot". It's base is a mixture of Norse, Galic, Celtic, Latin, Saxon, French and Bretton.
So we have no problem with it acquiring influences from other cultures it comes into contact with. Though the differences between British English and American English, "Hood" = "Bonnet", "Side walk" = "Pavement", "Pavement" = "Road", "Trunk" = "Boot", "Eraser" = "Rubber", "Rubber" = "Condom" etc. can also be very confusing. XD
I was always told off for referring to a "rule" as a "ruler" in school, as that is an Americanism. A "rule" is a measuring instrument, a "ruler" is a person in charge. Now, most British people would call a "rule" a "ruler". I was also chastised (by my parents) for using the word "ain't" for it's being "bad English", and I should use the word "isn't" instead. However, from "The Scarlet Pimpernel" the character of "Sir Percy Blakeney" frequently flourishes the word "ain't", as a popular high-class term.
So the evolution is on-going. The language is still a living, evolving thing.