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I must have superseded you must have superseded he must have superseded we must have superseded you must have superseded they must have superseded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I mustn't have superseded you mustn't have superseded he mustn't have superseded we mustn't have superseded you mustn't have superseded they mustn't have superseded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must I have superseded? must you have superseded? must he have superseded? must we have superseded? must you have superseded? must they have superseded?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mustn't I have superseded? mustn't you have superseded? mustn't he have superseded? mustn't we have superseded? mustn't you have superseded?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