At the risk of driving you up the wall, but please explain

One simple example is slavic languages where you have different forms of plural depending on the number.

Not the parent, but you use a translation format like `translations("INVITE_USER", {gender_of_host, num_guests})`

Then you will have an algorithm that knows to translate based on some rules - like the ICU messages format - https://unicode-org.github.io/icu/userguide/format_parse/mes...

In the link there's an example of how such rules look like (they'll be different for each language)

Making it plural doesn't always mean "replace one word by another".

The right thing to do it:

add_one = "Add one thing" add_multiple = "Add {n} things"

Then you'll provide the full sentence for each language. Of course some languages will need more cases, like slavic language where it's 1, 2-4, 5+, so depending on the languages you need to support you need to put more than 2 strings.

pluralization is much MUCH more complex in many languages than in English: https://www.unicode.org/cldr/charts/47/supplemental/language...

it can largely be turned into six categories of behavior, with tons of languages choosing different boundaries for those categories. ios/osx and android have tools for this, and probably others (I'm just personally familiar with these).

and even English isn't even that simple in the way many treat it - you don't pluralize sentences, parts of sentences change in contrast to each other (a car drives vs cars drive). so e.g. widely used APIs like https://apidock.com/rails/v7.1.3.4/String/pluralize are blatantly misleading merely by existing, and it leads to mistakes in many (most?) languages, and also English, even though the authors of the API speak English.

For example, in Arabic, nouns have three forms: singular, dual, and plural. Dual and plural are not interchangeable.