must corroborate
Regular verb: corroborate - corroborated- corroborated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must corroborate
you must corroborate
she must corroborate
we must corroborate
you must corroborate
they must corroborate 	I must be corroborating
you must be corroborating
she must be corroborating
we must be corroborating
you must be corroborating
they must be corroborating	I must have corroborated
you must have corroborated
she must have corroborated
we must have corroborated
you must have corroborated
they must have corroborated	I must have been corroborating
you must have been corroborating
she must have been corroborating
we must have been corroborating
you must have been corroborating
they must have been corroborating	

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

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I corroborate?
must you corroborate?
must she corroborate?
must we corroborate?
must you corroborate?
must they corroborate? 	must I be corroborating?
must you be corroborating?
must she be corroborating?
must we be corroborating?
must you be corroborating?
must they be corroborating? 	must I have corroborated?
must you have corroborated?
must she have corroborated?
must we have corroborated?
must you have corroborated?
must they have corroborated? 	must I have been corroborating?
must you have been corroborating?
must she have been corroborating?
must we have been corroborating?
must you have been corroborating?
must they have been corroborating? 	

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