Well, story Point of View can help considerably. Meaning, the character who's PoV it is can respond in ways that informs the reader what the other characters said, or they internalize it with thoughts concerning their own responses, and so on.
"Ublee bublee, boo looblay lah," Bob said with a pleading smile.
Mary shook her head at Bob's request, "I'm not going to give you my last candy bar. And you're not starving." She always knew he was a chocoholic, but he had never begged for her candy like that.<<<PoV character
It might not be an exact translation, but the message comes across nevertheless. You also have an advantage in that the characters are bi-lingual so though they might speak in some other language they can still think in English. Granted, that's not exactly how folks really do it. But, in that way the reader can follow along.
Be careful though. If
all of your dialogue cannot be understood by the reader, I'd bet they'll give up reading. So, use just little bits to add some spice to the story without overwhelming it.
In my current work I have two made up languages and multiple real non-English languages. Times when the PoV character doesn't know what the other character is saying, I don't help the reader to understand. Other cases, my PoV-C does something similar to above, others she might repeat what the other character says internally or externally, she might physically react, all sorts of ways...BUT...Though I have a pages of exact translations **see below**, by word cross referencing glossaries, etc., for the most part I rely on my story to convey the meaning.
** After each passage containing a non-English language I add a reference/footnote marker like this:
“Po’, yawut Meircan?” Pogue bawled, still laughing. “Un ats P-say wha pes. Welp, P-say Sowfilly style, Sowfee-say. As mi say, mi from ‘ere, mi ahways bint ‘ere. Mae’ say G-tahk fo Meircan.”
[T2F]
In a print version's appendices (I don't want to clutter story pages with footnotes), there are pages of translations in order:
2F. “Po’, yawut Meircan?” Pogue bawled, still laughing. “Un ats P-say wha pes. Welp, P-say Sowfilly style, Sowfee-say. As mi say, mi from ‘ere, mi ahways bint ‘ere. Mae’ say G-tahk fo Meircan.”
T: “You mean English?” Pogue bawled, still laughing. “And it’s People's Language what else. Well, People's Language South Philly style, South Philadelphia pidgin dialect. Like I said, I’m from here, I’ve always been here. We say Government Language for English.”
In a
perfect world, in digital versions, a hover over the footnote would cause a popup:
However, since that popup option is not available (that I know of), I'll NOT
link> to somewhere else.
Point being, I don't want my reader to read a line, then look up a translation, read a few more lines, then look up another translation again. I want them to read the story and if they want to see full translations, they can look it up after (so, I must make it actually inconvenient).
If that's the case, then the reader MUST be able to follow the story without a hiccup/pause and still understand what is happening and what was meant in the non-English passage. So, those non-English passages MUST inspire direct responses which explain it, inspire action reacting to it, or feel like background clutter JUST as they seem to the PoV character.
Anywho, just my opinion.
I am NOT a published author like many others here are.
K2