must firm
Verbe régulier : firm - firmed- firmed
Traduction française : tasser - se raffermir 

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I must firm
you must firm
he must firm
we must firm
you must firm
they must firm 	I must be firming
you must be firming
he must be firming
we must be firming
you must be firming
they must be firming	I must have firmed
you must have firmed
he must have firmed
we must have firmed
you must have firmed
they must have firmed	I must have been firming
you must have been firming
he must have been firming
we must have been firming
you must have been firming
they must have been firming	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I mustn't firm
you mustn't firm
he mustn't firm
we mustn't firm
you mustn't firm
they mustn't firm 	I mustn't be firming
you mustn't be firming
he mustn't be firming
we mustn't be firming
you mustn't be firming
they mustn't be firming	I mustn't have firmed
you mustn't have firmed
he mustn't have firmed
we mustn't have firmed
you mustn't have firmed
they mustn't have firmed	I mustn't have been firming
you mustn't have been firming
he mustn't have been firming
we mustn't have been firming
you mustn't have been firming
they mustn't have been firming	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
must I firm?
must you firm?
must he firm?
must we firm?
must you firm?
must they firm? 	must I be firming?
must you be firming?
must he be firming?
must we be firming?
must you be firming?
must they be firming? 	must I have firmed?
must you have firmed?
must he have firmed?
must we have firmed?
must you have firmed?
must they have firmed? 	must I have been firming?
must you have been firming?
must he have been firming?
must we have been firming?
must you have been firming?
must they have been firming? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
mustn't I firm?
mustn't you firm?
mustn't he firm?
mustn't we firm?
mustn't you firm?
mustn't they firm? 	mustn't I be firming?
mustn't you be firming?
mustn't he be firming?
mustn't we be firming?
mustn't you be firming?
mustn't they be firming? 	mustn't I have firmed?
mustn't you have firmed?
mustn't he have firmed?
mustn't we have firmed?
mustn't you have firmed?
mustn't they have firmed? 	mustn't I have been firming?
mustn't you have been firming?
mustn't he have been firming?
mustn't we have been firming?
mustn't you have been firming?
mustn't they have been firming?