should undergird
Irregular verb: undergird - undergirt, undergirded- undergirt, undergirded

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I'd undergird
you'd undergird
he'd undergird
we'd undergird
you'd undergird
they'd undergird 	I'd be undergirding
you'd be undergirding
he'd be undergirding
we'd be undergirding
you'd be undergirding
they'd be undergirding	I should've undergirt, undergirded
you should've undergirt, undergirded
he should've undergirt, undergirded
we should've undergirt, undergirded
you should've undergirt, undergirded
they should've undergirt, undergirded	I should've been undergirding
you should've been undergirding
he should've been undergirding
we should've been undergirding
you should've been undergirding
they should've been undergirding	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I shouldn't undergird
you shouldn't undergird
he shouldn't undergird
we shouldn't undergird
you shouldn't undergird
they shouldn't undergird 	I shouldn't be undergirding
you shouldn't be undergirding
he shouldn't be undergirding
we shouldn't be undergirding
you shouldn't be undergirding
they shouldn't be undergirding	I shouldn't have undergirt, undergirded
you shouldn't have undergirt, undergirded
he shouldn't have undergirt, undergirded
we shouldn't have undergirt, undergirded
you shouldn't have undergirt, undergirded
they shouldn't have undergirt, undergirded	I shouldn't have been undergirding
you shouldn't have been undergirding
he shouldn't have been undergirding
we shouldn't have been undergirding
you shouldn't have been undergirding
they shouldn't have been undergirding	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I undergird?
should you undergird?
should he undergird?
should we undergird?
should you undergird?
should they undergird? 	should I be undergirding?
should you be undergirding?
should he be undergirding?
should we be undergirding?
should you be undergirding?
should they be undergirding? 	should I have undergirt, undergirded?
should you have undergirt, undergirded?
should he have undergirt, undergirded?
should we have undergirt, undergirded?
should you have undergirt, undergirded?
should they have undergirt, undergirded? 	should I have been undergirding?
should you have been undergirding?
should he have been undergirding?
should we have been undergirding?
should you have been undergirding?
should they have been undergirding? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
shouldn't I undergird?
shouldn't you undergird?
shouldn't he undergird?
shouldn't we undergird?
shouldn't you undergird?
shouldn't they undergird? 	shouldn't I be undergirding?
shouldn't you be undergirding?
shouldn't he be undergirding?
shouldn't we be undergirding?
shouldn't you be undergirding?
shouldn't they be undergirding? 	shouldn't I have undergirt, undergirded?
shouldn't you have undergirt, undergirded?
shouldn't he have undergirt, undergirded?
shouldn't we have undergirt, undergirded?
shouldn't you have undergirt, undergirded?
shouldn't they have undergirt, undergirded? 	shouldn't I have been undergirding?
shouldn't you have been undergirding?
shouldn't he have been undergirding?
shouldn't we have been undergirding?
shouldn't you have been undergirding?
shouldn't they have been undergirding?