I must drum you must drum she must drum we must drum you must drum they must drum
V-ing form
I must be drumming you must be drumming she must be drumming we must be drumming you must be drumming they must be drumming
Perfect
I must have drummed you must have drummed she 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 she must have been drumming we must have been drumming you must have been drumming they must have been drumming
Negation
Simple form
I must not drum you must not drum she must not drum we must not drum you must not drum they must not drum
V-ing form
I must not be drumming you must not be drumming she must not be drumming we must not be drumming you must not be drumming they must not be drumming
Perfect
I must not have drummed you must not have drummed she must not have drummed we must not have drummed you must not have drummed they must not have drummed
V-ing perfect
I must not have been drumming you must not have been drumming she must not have been drumming we must not have been drumming you must not have been drumming they must not have been drumming
Interrogative form
Simple form
must I drum? must you drum? must she drum? must we drum? must you drum? must they drum?
V-ing form
must I be drumming? must you be drumming? must she be drumming? must we be drumming? must you be drumming? must they be drumming?
Perfect
must I have drummed? must you have drummed? must she 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 she have been drumming? must we have been drumming? must you have been drumming? must they have been drumming?
Interro-negative form
Simple form
must I not drum? must you not drum? must she not drum? must we not drum? must you not drum? must they not drum?
V-ing form
must I not be drumming? must you not be drumming? must she not be drumming? must we not be drumming? must you not be drumming? must they not be drumming?
Perfect
must I not have drummed? must you not have drummed? must she not have drummed? must we not have drummed? must you not have drummed? must they not have drummed?
V-ing perfect
must I not have been drumming? must you not have been drumming? must she not have been drumming? must we not have been drumming? must you not have been drumming? must they not have been drumming?