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