must concentrate
Verbe régulier : concentrate - concentrated- concentrated
Traduction française : se concentrer - concentrer 

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I must concentrate
you must concentrate
he must concentrate
we must concentrate
you must concentrate
they must concentrate 	I must be concentrating
you must be concentrating
he must be concentrating
we must be concentrating
you must be concentrating
they must be concentrating	I must have concentrated
you must have concentrated
he must have concentrated
we must have concentrated
you must have concentrated
they must have concentrated	I must have been concentrating
you must have been concentrating
he must have been concentrating
we must have been concentrating
you must have been concentrating
they must have been concentrating	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I mustn't concentrate
you mustn't concentrate
he mustn't concentrate
we mustn't concentrate
you mustn't concentrate
they mustn't concentrate 	I mustn't be concentrating
you mustn't be concentrating
he mustn't be concentrating
we mustn't be concentrating
you mustn't be concentrating
they mustn't be concentrating	I mustn't have concentrated
you mustn't have concentrated
he mustn't have concentrated
we mustn't have concentrated
you mustn't have concentrated
they mustn't have concentrated	I mustn't have been concentrating
you mustn't have been concentrating
he mustn't have been concentrating
we mustn't have been concentrating
you mustn't have been concentrating
they mustn't have been concentrating	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
must I concentrate?
must you concentrate?
must he concentrate?
must we concentrate?
must you concentrate?
must they concentrate? 	must I be concentrating?
must you be concentrating?
must he be concentrating?
must we be concentrating?
must you be concentrating?
must they be concentrating? 	must I have concentrated?
must you have concentrated?
must he have concentrated?
must we have concentrated?
must you have concentrated?
must they have concentrated? 	must I have been concentrating?
must you have been concentrating?
must he have been concentrating?
must we have been concentrating?
must you have been concentrating?
must they have been concentrating? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
mustn't I concentrate?
mustn't you concentrate?
mustn't he concentrate?
mustn't we concentrate?
mustn't you concentrate?
mustn't they concentrate? 	mustn't I be concentrating?
mustn't you be concentrating?
mustn't he be concentrating?
mustn't we be concentrating?
mustn't you be concentrating?
mustn't they be concentrating? 	mustn't I have concentrated?
mustn't you have concentrated?
mustn't he have concentrated?
mustn't we have concentrated?
mustn't you have concentrated?
mustn't they have concentrated? 	mustn't I have been concentrating?
mustn't you have been concentrating?
mustn't he have been concentrating?
mustn't we have been concentrating?
mustn't you have been concentrating?
mustn't they have been concentrating?