Suppose there is a sentence in question form, like the one appearing below:
Where do you belong to?
Now, if a speaker refers to that question, he will frame another sentence and will place the question in the quotation marks in that sentence, like what is appearing below:
They said, "Where do you belong to?"
Now, if the speaker wants to convert this sentence too in question form, he will put the original question in another question, like what is appearing below:
What did they mean by saying "Where do you belong to?"
Now, if the speaker wants to rephrase this sentence, it would become as follows:
By saying "Where do you belong to?" what did they mean?
My question is how the 4th sentence is to be punctuated. It has two question marks in it. Does the sentence correctly take two question marks? If so, why will the 3rd sentence not take two question marks − one, just before the closing inverted commas and, the second, just after those commas? The 4th sentence and the 3rd sentence are all same, except being a bit different in placement of the words. Will they take two different sets of punctuation marks?