I can corroborate you can corroborate he can corroborate we can corroborate you can corroborate they can corroborate
V-ing form
I can be corroborating you can be corroborating he can be corroborating we can be corroborating you can be corroborating they can be corroborating
Perfect
I can have corroborated you can have corroborated he can have corroborated we can have corroborated you can have corroborated they can have corroborated
V-ing perfect
I can have been corroborating you can have been corroborating he can have been corroborating we can have been corroborating you can have been corroborating they can have been corroborating
Negation
Simple form
I cannot corroborate you cannot corroborate he cannot corroborate we cannot corroborate you cannot corroborate they cannot corroborate
V-ing form
I cannot be corroborating you cannot be corroborating he cannot be corroborating we cannot be corroborating you cannot be corroborating they cannot be corroborating
Perfect
I cannot have corroborated you cannot have corroborated he cannot have corroborated we cannot have corroborated you cannot have corroborated they cannot have corroborated
V-ing perfect
I cannot have been corroborating you cannot have been corroborating he cannot have been corroborating we cannot have been corroborating you cannot have been corroborating they cannot have been corroborating
Interrogative form
Simple form
can I corroborate? can you corroborate? can he corroborate? can we corroborate? can you corroborate? can they corroborate?
V-ing form
can I be corroborating? can you be corroborating? can he be corroborating? can we be corroborating? can you be corroborating? can they be corroborating?
Perfect
can I have corroborated? can you have corroborated? can he have corroborated? can we have corroborated? can you have corroborated? can they have corroborated?
V-ing perfect
can I have been corroborating? can you have been corroborating? can he have been corroborating? can we have been corroborating? can you have been corroborating? can they have been corroborating?
Interro-negative form
Simple form
can I not corroborate? can you not corroborate? can he not corroborate? can we not corroborate? can you not corroborate? can they not corroborate?
V-ing form
can I not be corroborating? can you not be corroborating? can he not be corroborating? can we not be corroborating? can you not be corroborating? can they not be corroborating?
Perfect
can I not have corroborated? can you not have corroborated? can he not have corroborated? can we not have corroborated? can you not have corroborated? can they not have corroborated?
V-ing perfect
can I not have been corroborating? can you not have been corroborating? can he not have been corroborating? can we not have been corroborating? can you not have been corroborating? can they not have been corroborating?