Why we say"What happened ?" instead of "What did happen"?

I have asked this question in Y Q and they said "What happened" is the correct one.

Why ?

Do you have any rule to follow for this kind of situation please?

Thanks a lot.
Full Member107
Don't add do, does, or did when the question word (what in this case) is the subject of the sentence.

What did Jack say? Jack is the subject. What is not the subject.

What happened? What is the subject.

Who does he look like? he is the subject. Who is not the subject.

Who looks like me? Who is the subject.

Which forks do you place next to the plate? you is the subject. Which forks is not the subject.

Which forks go next to the plate? Which forks is the subject.

CJ
Veteran Member53,291
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austere125rivers"What did happen"?
Actually, this is used for emphatic expression (surprise, shock, disbelief).

So if that didn't happen, then what DID happen?
Veteran Member22,735
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You are the best! Thank you so much Calif !All your anwers are backed with proofs.

Do you have any grammar books ??
austere125riversDo you have any grammar books ?
See my response to your other post. I'm not in a position to advise anyone on this topic. Sorry.

CJ
Moderator: A super-user who takes care of the forums. You have the ability to message a moderator privately should you wish. These users have a range of elevated privileges including the deletion, editing and movement of posts when needed.Proficient Speaker: Users in this role are known to maintain an excellent grasp of the English language. You can only be promoted to this role by the Englishforums team.
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