ought to underpin
Regular verb: underpin - underpinned- underpinned

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I ought to underpin
you ought to underpin
she ought to underpin
we ought to underpin
you ought to underpin
they ought to underpin 	I ought to be underpinning
you ought to be underpinning
she ought to be underpinning
we ought to be underpinning
you ought to be underpinning
they ought to be underpinning	I ought to have underpinned
you ought to have underpinned
she ought to have underpinned
we ought to have underpinned
you ought to have underpinned
they ought to have underpinned	I ought to have been underpinning
you ought to have been underpinning
she ought to have been underpinning
we ought to have been underpinning
you ought to have been underpinning
they ought to have been underpinning	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I oughtn't to underpin
you oughtn't to underpin
she oughtn't to underpin
we oughtn't to underpin
you oughtn't to underpin
they oughtn't to underpin 	I oughtn't to be underpinning
you oughtn't to be underpinning
she oughtn't to be underpinning
we oughtn't to be underpinning
you oughtn't to be underpinning
they oughtn't to be underpinning	I oughtn't to have underpinned
you oughtn't to have underpinned
she oughtn't to have underpinned
we oughtn't to have underpinned
you oughtn't to have underpinned
they oughtn't to have underpinned	I oughtn't to have been underpinning
you oughtn't to have been underpinning
she oughtn't to have been underpinning
we oughtn't to have been underpinning
you oughtn't to have been underpinning
they oughtn't to have been underpinning	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
ought to I underpin?
ought to you underpin?
ought to she underpin?
ought to we underpin?
ought to you underpin?
ought to they underpin? 	ought to I be underpinning?
ought to you be underpinning?
ought to she be underpinning?
ought to we be underpinning?
ought to you be underpinning?
ought to they be underpinning? 	ought to I have underpinned?
ought to you have underpinned?
ought to she have underpinned?
ought to we have underpinned?
ought to you have underpinned?
ought to they have underpinned? 	ought to I have been underpinning?
ought to you have been underpinning?
ought to she have been underpinning?
ought to we have been underpinning?
ought to you have been underpinning?
ought to they have been underpinning? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
oughtn't I to underpin?
oughtn't you to underpin?
oughtn't she to underpin?
oughtn't we to underpin?
oughtn't you to underpin?
oughtn't they to underpin? 	oughtn't I to be underpinning?
oughtn't you to be underpinning?
oughtn't she to be underpinning?
oughtn't we to be underpinning?
oughtn't you to be underpinning?
oughtn't they to be underpinning? 	oughtn't I to have underpinned?
oughtn't you to have underpinned?
oughtn't she to have underpinned?
oughtn't we to have underpinned?
oughtn't you to have underpinned?
oughtn't they to have underpinned? 	oughtn't I to have been underpinning?
oughtn't you to have been underpinning?
oughtn't she to have been underpinning?
oughtn't we to have been underpinning?
oughtn't you to have been underpinning?
oughtn't they to have been underpinning?