must underinsure
Regular verb: underinsure - underinsured- underinsured

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must underinsure
you must underinsure
he must underinsure
we must underinsure
you must underinsure
they must underinsure 	I must be underinsuring
you must be underinsuring
he must be underinsuring
we must be underinsuring
you must be underinsuring
they must be underinsuring	I must have underinsured
you must have underinsured
he must have underinsured
we must have underinsured
you must have underinsured
they must have underinsured	I must have been underinsuring
you must have been underinsuring
he must have been underinsuring
we must have been underinsuring
you must have been underinsuring
they must have been underinsuring	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't underinsure
you mustn't underinsure
he mustn't underinsure
we mustn't underinsure
you mustn't underinsure
they mustn't underinsure 	I mustn't be underinsuring
you mustn't be underinsuring
he mustn't be underinsuring
we mustn't be underinsuring
you mustn't be underinsuring
they mustn't be underinsuring	I mustn't have underinsured
you mustn't have underinsured
he mustn't have underinsured
we mustn't have underinsured
you mustn't have underinsured
they mustn't have underinsured	I mustn't have been underinsuring
you mustn't have been underinsuring
he mustn't have been underinsuring
we mustn't have been underinsuring
you mustn't have been underinsuring
they mustn't have been underinsuring	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I underinsure?
must you underinsure?
must he underinsure?
must we underinsure?
must you underinsure?
must they underinsure? 	must I be underinsuring?
must you be underinsuring?
must he be underinsuring?
must we be underinsuring?
must you be underinsuring?
must they be underinsuring? 	must I have underinsured?
must you have underinsured?
must he have underinsured?
must we have underinsured?
must you have underinsured?
must they have underinsured? 	must I have been underinsuring?
must you have been underinsuring?
must he have been underinsuring?
must we have been underinsuring?
must you have been underinsuring?
must they have been underinsuring? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I underinsure?
mustn't you underinsure?
mustn't he underinsure?
mustn't we underinsure?
mustn't you underinsure?
mustn't they underinsure? 	mustn't I be underinsuring?
mustn't you be underinsuring?
mustn't he be underinsuring?
mustn't we be underinsuring?
mustn't you be underinsuring?
mustn't they be underinsuring? 	mustn't I have underinsured?
mustn't you have underinsured?
mustn't he have underinsured?
mustn't we have underinsured?
mustn't you have underinsured?
mustn't they have underinsured? 	mustn't I have been underinsuring?
mustn't you have been underinsuring?
mustn't he have been underinsuring?
mustn't we have been underinsuring?
mustn't you have been underinsuring?
mustn't they have been underinsuring?