In some parts, class, education, station, ia / dia could be he she, although most default to ia for both, kalian and kamu are the same, except for "the" instead of "implied the" or "ini". Saya and Aku, again, parts of country, class, education and station. I've never heard anyone say Saya in the East, except in a formal letter
Because it's not grammatically correct in English. With singular, you have to use articles.
You write menus -> It works because it's a plural.
You write a menu. You write the menu.
Your error is about the lack of article in English with singular.
You write menus, could use the non-ambiguous plural form:
Kalian/kamu menulis menu-menu.
Or the ambiguous form "Kalian/kamu menulis menu".
In Indonesian, if you have menu-menu, it's only a plural, but if you have "menu" alone, you don't know if it's a singular, or an implied plural.
The main difference is "the" would refer to a specific item and "a" would be the item in general. It could be "a" menu, but in context, people don't generally write menus like they write letters and books, so it's more likely it's a specific menu being discussed. Anyway, that's my interpretation.
I disagree. There's no reason you couldn't write a menu. It's grammatically correct, and possible.
If you have several menus to write, for instance one for children, and one with vegetarian dishes, you write one of them: you write a menu.
For their sentence, Kalian menulis menu, could be a menu, the menu, menus or the menus. As there's no article and no indications in Indonesian.
I agree that it is possible to write a menu, certainly in the context you suggest. But with no other context provided, it makes more sense to me, as a native speaker, to say "the menu." This may be because English has the expression "What's on the menu?" with the context implied, not specified. I agree with your point that to know for sure what is being expressed by the Indonesian phrase, you would need to know the speaker's context.
Yes Michelle, I do agree. One meaning is more obvious, and common than the other, not only in English. I don't think it's only because of the expression "qu'est-ce qui est au menu?". It's more common to write the menu, than several ones. But it forces us to think. If the sentence is grammatically okay, and a context is possible (even a rare one), this has to be considered as a valid alternative solution.