I could corroborate you could corroborate he could corroborate we could corroborate you could corroborate they could corroborate
Forme en V-ing
I could be corroborating you could be corroborating he could be corroborating we could be corroborating you could be corroborating they could be corroborating
Perfect
I could have corroborated you could have corroborated he could have corroborated we could have corroborated you could have corroborated they could have corroborated
Perfect en V-ing
I could have been corroborating you could have been corroborating he could have been corroborating we could have been corroborating you could have been corroborating they could have been corroborating
Négation
Forme simple
I could not corroborate you could not corroborate he could not corroborate we could not corroborate you could not corroborate they could not corroborate
Forme en V-ing
I could not be corroborating you could not be corroborating he could not be corroborating we could not be corroborating you could not be corroborating they could not be corroborating
Perfect
I could not have corroborated you could not have corroborated he could not have corroborated we could not have corroborated you could not have corroborated they could not have corroborated
Perfect en V-ing
I could not have been corroborating you could not have been corroborating he could not have been corroborating we could not have been corroborating you could not have been corroborating they could not have been corroborating
Forme interrogative
Forme simple
could I corroborate? could you corroborate? could he corroborate? could we corroborate? could you corroborate? could they corroborate?
Forme en V-ing
could I be corroborating? could you be corroborating? could he be corroborating? could we be corroborating? could you be corroborating? could they be corroborating?
Perfect
could I have corroborated? could you have corroborated? could he have corroborated? could we have corroborated? could you have corroborated? could they have corroborated?
Perfect en V-ing
could I have been corroborating? could you have been corroborating? could he have been corroborating? could we have been corroborating? could you have been corroborating? could they have been corroborating?
Forme interro-négative
Forme simple
could I not corroborate? could you not corroborate? could he not corroborate? could we not corroborate? could you not corroborate? could they not corroborate?
Forme en V-ing
could I not be corroborating? could you not be corroborating? could he not be corroborating? could we not be corroborating? could you not be corroborating? could they not be corroborating?
Perfect
could I not have corroborated? could you not have corroborated? could he not have corroborated? could we not have corroborated? could you not have corroborated? could they not have corroborated?
Perfect en V-ing
could I not have been corroborating? could you not have been corroborating? could he not have been corroborating? could we not have been corroborating? could you not have been corroborating? could they not have been corroborating?