I must drum you must drum he must drum we must drum you must drum they must drum
V-ing form
I must be drumming you must be drumming he must be drumming we must be drumming you must be drumming they must be drumming
Perfect
I must have drummed you must have drummed he must have drummed we must have drummed you must have drummed they must have drummed
V-ing perfect
I must have been drumming you must have been drumming he must have been drumming we must have been drumming you must have been drumming they must have been drumming
Negation
Simple form
I mustn't drum you mustn't drum he mustn't drum we mustn't drum you mustn't drum they mustn't drum
V-ing form
I mustn't be drumming you mustn't be drumming he mustn't be drumming we mustn't be drumming you mustn't be drumming they mustn't be drumming
Perfect
I mustn't have drummed you mustn't have drummed he mustn't have drummed we mustn't have drummed you mustn't have drummed they mustn't have drummed
V-ing perfect
I mustn't have been drumming you mustn't have been drumming he mustn't have been drumming we mustn't have been drumming you mustn't have been drumming they mustn't have been drumming
Interrogative form
Simple form
must I drum? must you drum? must he drum? must we drum? must you drum? must they drum?
V-ing form
must I be drumming? must you be drumming? must he be drumming? must we be drumming? must you be drumming? must they be drumming?
Perfect
must I have drummed? must you have drummed? must he have drummed? must we have drummed? must you have drummed? must they have drummed?
V-ing perfect
must I have been drumming? must you have been drumming? must he have been drumming? must we have been drumming? must you have been drumming? must they have been drumming?
Interro-negative form
Simple form
mustn't I drum? mustn't you drum? mustn't he drum? mustn't we drum? mustn't you drum? mustn't they drum?
V-ing form
mustn't I be drumming? mustn't you be drumming? mustn't he be drumming? mustn't we be drumming? mustn't you be drumming? mustn't they be drumming?
Perfect
mustn't I have drummed? mustn't you have drummed? mustn't he have drummed? mustn't we have drummed? mustn't you have drummed? mustn't they have drummed?
V-ing perfect
mustn't I have been drumming? mustn't you have been drumming? mustn't he have been drumming? mustn't we have been drumming? mustn't you have been drumming? mustn't they have been drumming?