I could degenerate you could degenerate she could degenerate we could degenerate you could degenerate they could degenerate
V-ing form
I could be degenerating you could be degenerating she could be degenerating we could be degenerating you could be degenerating they could be degenerating
Perfect
I could have degenerated you could have degenerated she could have degenerated we could have degenerated you could have degenerated they could have degenerated
V-ing perfect
I could have been degenerating you could have been degenerating she could have been degenerating we could have been degenerating you could have been degenerating they could have been degenerating
Negation
Simple form
I could not degenerate you could not degenerate she could not degenerate we could not degenerate you could not degenerate they could not degenerate
V-ing form
I could not be degenerating you could not be degenerating she could not be degenerating we could not be degenerating you could not be degenerating they could not be degenerating
Perfect
I could not have degenerated you could not have degenerated she could not have degenerated we could not have degenerated you could not have degenerated they could not have degenerated
V-ing perfect
I could not have been degenerating you could not have been degenerating she could not have been degenerating we could not have been degenerating you could not have been degenerating they could not have been degenerating
Interrogative form
Simple form
could I degenerate? could you degenerate? could she degenerate? could we degenerate? could you degenerate? could they degenerate?
V-ing form
could I be degenerating? could you be degenerating? could she be degenerating? could we be degenerating? could you be degenerating? could they be degenerating?
Perfect
could I have degenerated? could you have degenerated? could she have degenerated? could we have degenerated? could you have degenerated? could they have degenerated?
V-ing perfect
could I have been degenerating? could you have been degenerating? could she have been degenerating? could we have been degenerating? could you have been degenerating? could they have been degenerating?
Interro-negative form
Simple form
could I not degenerate? could you not degenerate? could she not degenerate? could we not degenerate? could you not degenerate? could they not degenerate?
V-ing form
could I not be degenerating? could you not be degenerating? could she not be degenerating? could we not be degenerating? could you not be degenerating? could they not be degenerating?
Perfect
could I not have degenerated? could you not have degenerated? could she not have degenerated? could we not have degenerated? could you not have degenerated? could they not have degenerated?
V-ing perfect
could I not have been degenerating? could you not have been degenerating? could she not have been degenerating? could we not have been degenerating? could you not have been degenerating? could they not have been degenerating?