I must background you must background he must background we must background you must background they must background
Forme en V-ing
I must be backgrounding you must be backgrounding he must be backgrounding we must be backgrounding you must be backgrounding they must be backgrounding
Perfect
I must have backgrounded you must have backgrounded he must have backgrounded we must have backgrounded you must have backgrounded they must have backgrounded
Perfect en V-ing
I must have been backgrounding you must have been backgrounding he must have been backgrounding we must have been backgrounding you must have been backgrounding they must have been backgrounding
Négation
Forme simple
I mustn't background you mustn't background he mustn't background we mustn't background you mustn't background they mustn't background
Forme en V-ing
I mustn't be backgrounding you mustn't be backgrounding he mustn't be backgrounding we mustn't be backgrounding you mustn't be backgrounding they mustn't be backgrounding
Perfect
I mustn't have backgrounded you mustn't have backgrounded he mustn't have backgrounded we mustn't have backgrounded you mustn't have backgrounded they mustn't have backgrounded
Perfect en V-ing
I mustn't have been backgrounding you mustn't have been backgrounding he mustn't have been backgrounding we mustn't have been backgrounding you mustn't have been backgrounding they mustn't have been backgrounding
Forme interrogative
Forme simple
must I background? must you background? must he background? must we background? must you background? must they background?
Forme en V-ing
must I be backgrounding? must you be backgrounding? must he be backgrounding? must we be backgrounding? must you be backgrounding? must they be backgrounding?
Perfect
must I have backgrounded? must you have backgrounded? must he have backgrounded? must we have backgrounded? must you have backgrounded? must they have backgrounded?
Perfect en V-ing
must I have been backgrounding? must you have been backgrounding? must he have been backgrounding? must we have been backgrounding? must you have been backgrounding? must they have been backgrounding?
Forme interro-négative
Forme simple
mustn't I background? mustn't you background? mustn't he background? mustn't we background? mustn't you background? mustn't they background?
Forme en V-ing
mustn't I be backgrounding? mustn't you be backgrounding? mustn't he be backgrounding? mustn't we be backgrounding? mustn't you be backgrounding? mustn't they be backgrounding?
Perfect
mustn't I have backgrounded? mustn't you have backgrounded? mustn't he have backgrounded? mustn't we have backgrounded? mustn't you have backgrounded? mustn't they have backgrounded?
Perfect en V-ing
mustn't I have been backgrounding? mustn't you have been backgrounding? mustn't he have been backgrounding? mustn't we have been backgrounding? mustn't you have been backgrounding? mustn't they have been backgrounding?