What food / snack from which area / ethnic group will you bring?
请问这里为什么既有 what,还在句子中间有
which 呢?
这是由句子语境的需要所导致的。
What food from which area 的意思是“来自哪个地方的什么食物”。
句意:
What food / snack from which area / ethnic group will you bring?
你会带什么来自哪个地区/民族的什么食物/零食?
类似的用法如:
Who or what set fire to the house? 是谁或者什么使房子着火的?
Where and when shall I pick you up? 我该在哪儿和什么时候接你呢?