Translation:What is your first name and last name?
It depends on how you translate the sentence. The conjunction word "and" does not denote plural usage, but rather the word "name." If "name" (singular) is used, then "What is..." is correct. If "names" (plural) is used, then one must use "What are..."
So grammatically correct options include: What is your first and last name? What are your first and last names?
The plural option, while grammatically correct, is not very natural sounding. Most people only have one first name and one last name. Using the word "and" simply takes two sentences (What is your first name? What is your last name?) and turns them into one sentence. But, you are still asking for one name at a time - first, and then last - and so using the singular form is more common and natural.
Sorry, that's not how I learned my mother tongue. The verb will not depend on a conjunction (why should it?) but on what functions as its subject and, of course, its object(s). Here, "what" clearly refers to a plurality, so "is" is understandable but bad english. Correct is "are". And I find it sounds natural.
The answer is much simpler, and depends on how we encode what we say as a list. Language is full of shortcuts, as it seeks to optimise data flow, as it were. So, uncompressed we get: What is your first name and [what is your] last name. When you look carefully, lists are a major operator, for what else are paragraphs but lists of sentences and books lists of chapters.
Please tell me where you found those revelations. Where in English speaking world last name means middle name?
EX Jan Kazimierz Waza
Jan - imię- first name/ given name
Kazimierz - drugie imię- middle name
Waza - nazwisko- last name/surname/family name
Maria Kazimiera Sobieska z domu d’Arquien
Maria - imię
Kazimiera- drugie imię
Sobieska - nazwisko ( "po mężu") - surname ("from husband")
d'Arquien- nazwisko panieńskie/nazwisko rodowe- maiden name/birth name
Very true. I am often around kids and rarely ask use this question. I would ask, What's your name? and if I needed a last name I would ask in a follow up question. That's why I thought it was weird that this wasn't a question normally asked of an adult. (Our experiences shape our perspective.)
does it though ? https://en.wikipedia.org/wiki/Family_name
I think you are talking about maiden name. Which in Poland is referred to as "nazwisko panieńskie", but now in legal documents it's "nazwisko rodowe", for gender equality. wikipedia says that :
"Birth name" is also used as a gender-neutral or masculine substitute for "maiden name."
but I see nothing about family name here. But wikipedia might be wrong, so please correct me, but link some resource.
Well, "Jak się nazywasz?" seems more probable than either "Jakie jest twoje..." or "Jak masz na...", actually. Although it risks that your interlocutor can answer only with the first name or the last name.
Putting the weirdness of saying "imię i nazwisko" in one sentence, "Jak masz na imię?" sounds a lot more natural and common to me than "Jakie jest twoje imię?".
In short, jak asks for an adverb (how?), whereas the various forms of jaki (what?) ask for adjectives.
"Jak się nazywasz?" literally translates to "How do you call yourself?"
"Jakie jest twoje imię?" would literally mean "What is your name?".
Of course the response in both cases includes a proper noun, but the adjective/adverb distinction still holds true in other contexts.
At first I was confused about what you mean, even though I understand the notion of "Christian name". I asked some UK natives and got this answer:
"Grammatically, I don't like it because 'name' is effectively missing after 'Christian', since it can't really be borrowed from 'surname'. "