I realise 'who saw you' is probably more common, but is 'who did see you' wrong? This is with respect to why who-questions don't need 'do'-support as an aux verb.

  • 2
    This is probably a duplicate of 'Which browsers do support this?' or 'Which browsers do support this?'?, itself closed as a duplicate. 'Who did see you?' is a marked emphatic form, used following a statement eg by the addressee that someone had seen them. It wouldn't be used as a mere replacement for 'Who saw you?' – Edwin Ashworth May 30 '17 at 7:26
  • I agree with the comment of @EdwinAshworth, and I'd add that this emphatic use of "did" would be likely to occur after negative statements. If you say "I was seen" but then you say "Alice didn't see me" and "Bob didn't see me" and "Charlie didn't see me" then I'd be inclined to aak "Well, who did see you?" – Andreas Blass Jul 30 '17 at 5:40

Word order with question word as subject (from PEU by Michael Swan):

When who, which, what or whose is the subject (or part of the subject), the question word comes before the verb, and do cannot normally be used.


Who left the door open? ( NOT Who did leave...?)

Which type of battery lasts longest? (NOT Which type of battery does last longest?)

What happened? (NOT What did happen?)

But do can be used after a subject question word for emphasis, to insist on an answer.

Well, tell us - what did happen when your father found you?

| improve this answer | |

Who saw you?


Who did you see?

mean completely different things.

In Who saw you?, who is the subject of the sentence, so the word who is in the nominative case.

In Who did you see?, who is actually the direct object of the sentence, so who is in the accusative case. You can understand this better if you convert the sentence like this:

You saw who?

One more thing worth telling: in Who did you see?, who is used in an informal manner, because the right form of the word who in the accusative case in formal English is whom.

So you sentence must actually be like this:

Whom did you see?

| improve this answer | |
  • 1
    Actually it was 'who did see you' – PolkaDot May 30 '17 at 7:18
  • 3
    Who did see you? is nothing more than a more emphatic way of saying Who saw you? – ΥΣΕΡ26328 May 30 '17 at 7:23
  • are you sure? I thought 'who did see you' was grammatically incorrect, as who is the subject? Not sure exactly why, but I don't think it is correct. – PolkaDot May 30 '17 at 7:24
  • 1
    Yes, I am very sure. – ΥΣΕΡ26328 May 30 '17 at 7:25
  • I expect most people to understand "who saw you" as "by whom were you seen" in normal use. – Davo May 30 '17 at 14:40

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.