must undervalue
Regular verb: undervalue - undervalued- undervalued

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must undervalue
you must undervalue
she must undervalue
we must undervalue
you must undervalue
they must undervalue 	I must be undervaluing
you must be undervaluing
she must be undervaluing
we must be undervaluing
you must be undervaluing
they must be undervaluing	I must have undervalued
you must have undervalued
she must have undervalued
we must have undervalued
you must have undervalued
they must have undervalued	I must have been undervaluing
you must have been undervaluing
she must have been undervaluing
we must have been undervaluing
you must have been undervaluing
they must have been undervaluing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't undervalue
you mustn't undervalue
she mustn't undervalue
we mustn't undervalue
you mustn't undervalue
they mustn't undervalue 	I mustn't be undervaluing
you mustn't be undervaluing
she mustn't be undervaluing
we mustn't be undervaluing
you mustn't be undervaluing
they mustn't be undervaluing	I mustn't have undervalued
you mustn't have undervalued
she mustn't have undervalued
we mustn't have undervalued
you mustn't have undervalued
they mustn't have undervalued	I mustn't have been undervaluing
you mustn't have been undervaluing
she mustn't have been undervaluing
we mustn't have been undervaluing
you mustn't have been undervaluing
they mustn't have been undervaluing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I undervalue?
must you undervalue?
must she undervalue?
must we undervalue?
must you undervalue?
must they undervalue? 	must I be undervaluing?
must you be undervaluing?
must she be undervaluing?
must we be undervaluing?
must you be undervaluing?
must they be undervaluing? 	must I have undervalued?
must you have undervalued?
must she have undervalued?
must we have undervalued?
must you have undervalued?
must they have undervalued? 	must I have been undervaluing?
must you have been undervaluing?
must she have been undervaluing?
must we have been undervaluing?
must you have been undervaluing?
must they have been undervaluing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I undervalue?
mustn't you undervalue?
mustn't she undervalue?
mustn't we undervalue?
mustn't you undervalue?
mustn't they undervalue? 	mustn't I be undervaluing?
mustn't you be undervaluing?
mustn't she be undervaluing?
mustn't we be undervaluing?
mustn't you be undervaluing?
mustn't they be undervaluing? 	mustn't I have undervalued?
mustn't you have undervalued?
mustn't she have undervalued?
mustn't we have undervalued?
mustn't you have undervalued?
mustn't they have undervalued? 	mustn't I have been undervaluing?
mustn't you have been undervaluing?
mustn't she have been undervaluing?
mustn't we have been undervaluing?
mustn't you have been undervaluing?
mustn't they have been undervaluing?