"Did you order tempe and eggs?"
Translation:Kamu pesan tempe dan telur?
"Apakah" is actually a great word to be added in the sentence to officially meet the formal Indonesian standards,
As in "Apakah kamu memesan tempe dan telur?"
But in spoken Indonesian, I think "apakah" won't be that necessary.
So I think Duolingo is just going to teach you spoken Indonesian more than the formal version.
Just a little side note:
"Apakah kamu yang memesan tempe dan telur?"
With adding "yang" in the sentence, the definition of the sentence becomes different. When translated to English, it becomes:
"Are you the one who ordered tempe and eggs?"
isn't there a better way to phrase this? e.g. in english you can say "you are driving BMW?" OR "are you driving a BMW?" Is there no question form of a sentence in Indonesian, or is there one which is taught later? Just repeating a statement in a questioning tone sounds not right
"Apakah kamu sudah pesan tempe dan telur?"
"Have you ordered tempe and eggs?"
It's like implying that whoever you were asking to had to order tempe and eggs
(Whether they wanted to or not, but by saying "Apakah kamu sudah pesan tempe dan telur?", it sounds more like if you were forcing them to order tempe and eggs then you asked them if they had done it or not.)
But if that's the case, it is more acceptable and proper if you say "Apa kamu sudah memesan/pesan tempe dan telur?".
Why is an explicit plural of eggs (telur-telur/telur2) not possible here?
If the dish is tempeh with two boiled eggs, rather than just one boiled egg - this kind of interaction is common in cafes and small fast-service restaurants where smaller or larger variants of dishes is available.
Because "telur-telur" isn't an acceptable plural form for eggs in Indonesian. Using "telur" to refer to the plural form of "egg" is acceptable.
The following example won't work with the question, but it's definitely a helpful tip.
Indonesian has a lot of singular articles, like "sebuah" (can be used for almost every object), "setangkai" (means "a branch", it's used mainly for flowers), "sebutir" (which is used for eggs or anything spherical), etc.
If you want to say "two eggs", you can use "dua butir telur". So never use "telur-telur", remember that this explicit plural concept can't be applied to everything.