I could cause you could cause she could cause we could cause you could cause they could cause
V-ing form
I could be causing you could be causing she could be causing we could be causing you could be causing they could be causing
Perfect
I could have caused you could have caused she could have caused we could have caused you could have caused they could have caused
V-ing perfect
I could have been causing you could have been causing she could have been causing we could have been causing you could have been causing they could have been causing
Negation
Simple form
I could not cause you could not cause she could not cause we could not cause you could not cause they could not cause
V-ing form
I could not be causing you could not be causing she could not be causing we could not be causing you could not be causing they could not be causing
Perfect
I could not have caused you could not have caused she could not have caused we could not have caused you could not have caused they could not have caused
V-ing perfect
I could not have been causing you could not have been causing she could not have been causing we could not have been causing you could not have been causing they could not have been causing
Interrogative form
Simple form
could I cause? could you cause? could she cause? could we cause? could you cause? could they cause?
V-ing form
could I be causing? could you be causing? could she be causing? could we be causing? could you be causing? could they be causing?
Perfect
could I have caused? could you have caused? could she have caused? could we have caused? could you have caused? could they have caused?
V-ing perfect
could I have been causing? could you have been causing? could she have been causing? could we have been causing? could you have been causing? could they have been causing?
Interro-negative form
Simple form
could I not cause? could you not cause? could she not cause? could we not cause? could you not cause? could they not cause?
V-ing form
could I not be causing? could you not be causing? could she not be causing? could we not be causing? could you not be causing? could they not be causing?
Perfect
could I not have caused? could you not have caused? could she not have caused? could we not have caused? could you not have caused? could they not have caused?
V-ing perfect
could I not have been causing? could you not have been causing? could she not have been causing? could we not have been causing? could you not have been causing? could they not have been causing?