The first is correct, but the second, though incorrect, is sometimes seen in print.
Is it proper to say "Did you use to smoke?" or Did you used to smoke? As far as I know the first from is the correct one. Please advise.
The first is correct, but the second, though incorrect, is sometimes seen in print.
Context is important. Please provide enough for us to be able to deal effectively with your question.
Your thread title should include all or part of the word/phrase being discussed.
If you just want to know the meaning of a word, try OneLook Dictionary Search first.
Used you to smoke? is also correct, but it's not heard much nowadays.