Colonel Edmund J. Burke wrote:
On 7/22/2018 9:22 AM, Jimmy Wilkinson Knife wrote:
On Sun, 22 Jul 2018 17:10:06 +0100, Colonel Edmund J. Burke wrote:

Who's on first.

That requires a question mark.

Did you know?

Did I know what?

It's a statement, not a question.

If it has a question mark, it's a question. 'Did you know' without a
question mark is ungrammatical as the auxiliary 'did' (past tense of 'do')
is (unless used transitively with a noun of action as the object, forming a
phrase similar to or equivalent to a related verb of action) serves as the
periphrastic form in interrogative sentences. The only exception to this
is in sentences where the question word itself is the subject of the verb.

It can also serve in elliptical use of a periphrastic auxiliary (or as an
auxiliary to a substitute or causal use of 'do') in past tenses.

Now, show us how bright you are, by shutting the _****_ up and not
responding to this post.

--
john smith |MA (Hons)|MPhil (Hons)|CAPES (mention très bien)|LLB (Hons)
'It never gets any easier. You just get faster'
(Greg LeMond (1961 - ))