Why in this question we do not use "did": Who brought you up? (instead of: Who did bring you up?)
And in this one we do: Who did you look up to? (instead of: Who you looked up to?)
thanks
Here is a detailed answer: https://www.englishforums.com/blog/who-brought-you-up/
The answer at that link is unsatisfactory.
It claims the following:
You ask "Who brought you up?" to get the answer in the subject position.
My aunt Sally brought me up.
You ask "Who did bring you up?" to get the answer in the object position.
The person who brought me up was my aunt Sally.
1) The use of "did" simply provides emphasis, especially when it is used after a negative.
— No, it was not my cousin Charlie who brought me up. And it wasn't my uncle Robert either.
— Well then who did bring you up?
— My aunt Sally brought me up.
2) Questioning the subject can be done with auxiliary do, but that is a matter unrelated to the fact that when you question the object you always need auxiliary do. The addition of 'did' to the given sentence means nothing remotely like a signal that the answer must be an object in the sentence given as a reply.
3) Aside from 'me' there is no object in the sentence
The person who brought me up was my aunt Sally.
'was' is a linking verb, so 'my aunt Sally' is not an object but a subject complement.
Those are just the glaring errors. There are also a few lesser ones.
CJ
It has to do with the role of "who". Is it the subject (as in Who brought you up?) or is it the object (as in Who did you look up to?)?
Here's a brief extract from a page from BBC Learning English that explains the differences between these two types of sentences: Compare:
Who saw you?>>> "Who" is the subject. You were seen by somebody.
Who did you see? >>> "Who" is the object. You saw somebody. (Strictly speaking, this one should be "Whom did you see?" ... but in everyday conversations "Who did you see?" is far more common).
Who brought you up? X brought me up.
Who did you look up to? I looked up to X.
If the word that answers the question is first in the answer, ask the question in the same order as the answer. Don't use do, does, or did.
(This is basically the same answer as Tanit gave. Tanit's is technically more correct. Mine is a good guideline.)
CJ
What about this sentence: Which bank offered him the best rate? I might answer: X bank offered him the best rate OR The best rate offered him X bank.
Do the same rules as above apply here?
CJ
CJ