Question words "Where" Can a preposition be at the end?

Question

Where did you play basketball?

Where did you go?

When it comes to "where", one of the question words, I know we don't put a preposition at the end because "where", I think, is a kind of adverb. At least, I have never heard

Where did you play basketball at?

Where did you go to?

In other cases, like "what" or "which", we can say

What did you do this for?

Which boy did you play games with?

However, I encountered one strange sentence on the net and is wondering why it is correct.

Where did you break in to?(I found it on grammar girl

Shouldn't it be "where did you break in"?

Grammar girl website(where I found the sentence): http://www.quickanddirtytips.com/education/grammar/in-to-or-into?page=1

Where are you from?

Maybe I sound stupid, but I am curious about why the "from" can be there.

Answer 1

Where did you play basketball at?

This is okay. The at is not necessary, but it is normal in some people's dialects. You might want to avoid it, unless you want to sound dialectal. This advice applies to writing, not just speaking.

Where did you go to?

This is commonly used. For example: in the sense of trying to find a lost pet or even a lost object: Now where did you go to? Or Where did you get to? or Where did you go/run off to? It is a rearrangement of "To where did you do?", which sounds rather stuffy.

What did you do this for?

This is natural and common. 'What for' or 'for what' can have the same meaning as 'why', so this is fine and means the same as "Why did you do this?"

Which boy did you play games with?

is rearranged from the rather stuffy

With which boy did you play games?

As for

Where did you break in to?

Grammar Girl's explanation, in this case, is fine.

Where are you from?

is perfectly normal English. It would be weird and unusual to say or hear "From where are you?"

You want to know why Where are you from? is okay? This is one of those answers that amounts to because this is how we say it. Please note that in informal language it is acceptable to end a sentence in a preposition.

Answer 2

English snobs will tell you to avoid ending sentences in prepositions at all times. However, modern spoken and written English breaks this rule frequently. So I wouldn't worry too much about placing prepositions at the end of sentences at all (unless you are very concerned about older, over-educated speakers' judging your English).

The "correct" way to phrase the last sentence you posted would be "From where are you?" However, this sounds a little odd and would be more indicative of a romance language construction (such as in French or Spanish).

As to your other sentence of interest, "Where did you break in to?" I agree with you completely that "Where did you break in?" makes more sense, so in this case you can rationalize the difference as a matter of preference. In other words, it doesn't matter, chose which one you prefer.

The grammar girl article to which you linked, was focusing on the distinction between 'into' and 'in to' so I think she included the extra 'to' in that last sentence as a means to demonstrate the difference.

Hopefully that was helpful!