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