Question

everyone must obay the rules. question tag​

Answer 1

Everyone must obey the rules, mustn't they?

A question tag should be added in a way that if the statement is positive or negative the tag should be negative or positive respectively.

Example,

He is sweet, isn't he?

He isn't sweet, is he?

Answer 2

$\huge\bold\red{RUDEBOY}$

Everyone must obey the rules , must'nt they ?

Or

Everyone must obey the rules , isn't they ?