must underuse
Verbo regolare: underuse - underused- underused

Affermazione 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
I must underuse
you must underuse
he must underuse
we must underuse
you must underuse
they must underuse 	I must be underusing
you must be underusing
he must be underusing
we must be underusing
you must be underusing
they must be underusing	I must have underused
you must have underused
he must have underused
we must have underused
you must have underused
they must have underused	I must have been underusing
you must have been underusing
he must have been underusing
we must have been underusing
you must have been underusing
they must have been underusing	

Negazione 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
I mustn't underuse
you mustn't underuse
he mustn't underuse
we mustn't underuse
you mustn't underuse
they mustn't underuse 	I mustn't be underusing
you mustn't be underusing
he mustn't be underusing
we mustn't be underusing
you mustn't be underusing
they mustn't be underusing	I mustn't have underused
you mustn't have underused
he mustn't have underused
we mustn't have underused
you mustn't have underused
they mustn't have underused	I mustn't have been underusing
you mustn't have been underusing
he mustn't have been underusing
we mustn't have been underusing
you mustn't have been underusing
they mustn't have been underusing	

Forma interrogativa 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
must I underuse?
must you underuse?
must he underuse?
must we underuse?
must you underuse?
must they underuse? 	must I be underusing?
must you be underusing?
must he be underusing?
must we be underusing?
must you be underusing?
must they be underusing? 	must I have underused?
must you have underused?
must he have underused?
must we have underused?
must you have underused?
must they have underused? 	must I have been underusing?
must you have been underusing?
must he have been underusing?
must we have been underusing?
must you have been underusing?
must they have been underusing? 	

Forma interro-negativa 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
mustn't I underuse?
mustn't you underuse?
mustn't he underuse?
mustn't we underuse?
mustn't you underuse?
mustn't they underuse? 	mustn't I be underusing?
mustn't you be underusing?
mustn't he be underusing?
mustn't we be underusing?
mustn't you be underusing?
mustn't they be underusing? 	mustn't I have underused?
mustn't you have underused?
mustn't he have underused?
mustn't we have underused?
mustn't you have underused?
mustn't they have underused? 	mustn't I have been underusing?
mustn't you have been underusing?
mustn't he have been underusing?
mustn't we have been underusing?
mustn't you have been underusing?
mustn't they have been underusing?