[Grammar] You do not must play here

[Aidan]

The Sentence “You do not must play here” ​is incorrect.
Can you tell me a) which grammatical rule is broken and b) how to work out which grammatical rule is broken.

My guess is that the Adverb of negation ‘not’ comes after the modal verb ‘must’ and before the main verb ‘eat’. In this case the auxiliary verb ‘do’ is not required as it’s position replaced by modal verb ‘must’.

c) Is my guess correct? If it is, is there a better way to explain the grammatical error with reference to a specific rule?

 

[TheParser]

NOT A TEACHER

You play here.
You do play here.
You do not play here.

You play here.
You must play here.
You must not play here.

 

[Chicken Sandwich]

***NOT A TEACHER***

Your sentence contains too many verbs. "Do" is redundant and "not" should be placed after must (musn't or must not). I don't know if this is a "rule", but this is the usual word order in English.

 

[tzfujimino]

NOT A TEACHER

You play here.
You do play here.
You do not play here.

You play here.
You must play here.
You must not play here.

Very simple and precise, indeed!:-D

 

[5jj]

We never use DO as an auxiliary with the core modals (can, could, may, might, must, shall, should,will, would).