ought to corroborate
Regular verb: corroborate - corroborated- corroborated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I ought to corroborate
you ought to corroborate
he ought to corroborate
we ought to corroborate
you ought to corroborate
they ought to corroborate 	I ought to be corroborating
you ought to be corroborating
he ought to be corroborating
we ought to be corroborating
you ought to be corroborating
they ought to be corroborating	I ought to have corroborated
you ought to have corroborated
he ought to have corroborated
we ought to have corroborated
you ought to have corroborated
they ought to have corroborated	I ought to have been corroborating
you ought to have been corroborating
he ought to have been corroborating
we ought to have been corroborating
you ought to have been corroborating
they ought to have been corroborating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I oughtn't to corroborate
you oughtn't to corroborate
he oughtn't to corroborate
we oughtn't to corroborate
you oughtn't to corroborate
they oughtn't to corroborate 	I oughtn't to be corroborating
you oughtn't to be corroborating
he oughtn't to be corroborating
we oughtn't to be corroborating
you oughtn't to be corroborating
they oughtn't to be corroborating	I oughtn't to have corroborated
you oughtn't to have corroborated
he oughtn't to have corroborated
we oughtn't to have corroborated
you oughtn't to have corroborated
they oughtn't to have corroborated	I oughtn't to have been corroborating
you oughtn't to have been corroborating
he oughtn't to have been corroborating
we oughtn't to have been corroborating
you oughtn't to have been corroborating
they oughtn't to have been corroborating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
ought to I corroborate?
ought to you corroborate?
ought to he corroborate?
ought to we corroborate?
ought to you corroborate?
ought to they corroborate? 	ought to I be corroborating?
ought to you be corroborating?
ought to he be corroborating?
ought to we be corroborating?
ought to you be corroborating?
ought to they be corroborating? 	ought to I have corroborated?
ought to you have corroborated?
ought to he have corroborated?
ought to we have corroborated?
ought to you have corroborated?
ought to they have corroborated? 	ought to I have been corroborating?
ought to you have been corroborating?
ought to he have been corroborating?
ought to we have been corroborating?
ought to you have been corroborating?
ought to they have been corroborating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
oughtn't I to corroborate?
oughtn't you to corroborate?
oughtn't he to corroborate?
oughtn't we to corroborate?
oughtn't you to corroborate?
oughtn't they to corroborate? 	oughtn't I to be corroborating?
oughtn't you to be corroborating?
oughtn't he to be corroborating?
oughtn't we to be corroborating?
oughtn't you to be corroborating?
oughtn't they to be corroborating? 	oughtn't I to have corroborated?
oughtn't you to have corroborated?
oughtn't he to have corroborated?
oughtn't we to have corroborated?
oughtn't you to have corroborated?
oughtn't they to have corroborated? 	oughtn't I to have been corroborating?
oughtn't you to have been corroborating?
oughtn't he to have been corroborating?
oughtn't we to have been corroborating?
oughtn't you to have been corroborating?
oughtn't they to have been corroborating?