must act
Verbe régulier : act - acted- acted
Traduction française : agir - jouer 

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I must act
you must act
she must act
we must act
you must act
they must act 	I must be acting
you must be acting
she must be acting
we must be acting
you must be acting
they must be acting	I must have acted
you must have acted
she must have acted
we must have acted
you must have acted
they must have acted	I must have been acting
you must have been acting
she must have been acting
we must have been acting
you must have been acting
they must have been acting	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I mustn't act
you mustn't act
she mustn't act
we mustn't act
you mustn't act
they mustn't act 	I mustn't be acting
you mustn't be acting
she mustn't be acting
we mustn't be acting
you mustn't be acting
they mustn't be acting	I mustn't have acted
you mustn't have acted
she mustn't have acted
we mustn't have acted
you mustn't have acted
they mustn't have acted	I mustn't have been acting
you mustn't have been acting
she mustn't have been acting
we mustn't have been acting
you mustn't have been acting
they mustn't have been acting	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
must I act?
must you act?
must she act?
must we act?
must you act?
must they act? 	must I be acting?
must you be acting?
must she be acting?
must we be acting?
must you be acting?
must they be acting? 	must I have acted?
must you have acted?
must she have acted?
must we have acted?
must you have acted?
must they have acted? 	must I have been acting?
must you have been acting?
must she have been acting?
must we have been acting?
must you have been acting?
must they have been acting? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
mustn't I act?
mustn't you act?
mustn't she act?
mustn't we act?
mustn't you act?
mustn't they act? 	mustn't I be acting?
mustn't you be acting?
mustn't she be acting?
mustn't we be acting?
mustn't you be acting?
mustn't they be acting? 	mustn't I have acted?
mustn't you have acted?
mustn't she have acted?
mustn't we have acted?
mustn't you have acted?
mustn't they have acted? 	mustn't I have been acting?
mustn't you have been acting?
mustn't she have been acting?
mustn't we have been acting?
mustn't you have been acting?
mustn't they have been acting?