Yes ... English is unusual as most languages have a singular and a plural form for 'you'.
Fun story. "You" used to be plural only, but it was considered more formal than the singular "thou", so it took over. Ironically, now "thou" sounds more formal because basically the only places we hear it anymore are formal - the Bible and Shakespeare.
You write menu is not accepted as an answer, but "you write menus" is? Wouldn't it be "Kalian menulis menu-menu"?
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.