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 couldn't degenerate you couldn't degenerate she couldn't degenerate we couldn't degenerate you couldn't degenerate they couldn't degenerate
V-ing form
I couldn't be degenerating you couldn't be degenerating she couldn't be degenerating we couldn't be degenerating you couldn't be degenerating they couldn't be degenerating
Perfect
I couldn't have degenerated you couldn't have degenerated she couldn't have degenerated we couldn't have degenerated you couldn't have degenerated they couldn't have degenerated
V-ing perfect
I couldn't have been degenerating you couldn't have been degenerating she couldn't have been degenerating we couldn't have been degenerating you couldn't have been degenerating they couldn't 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
couldn't I degenerate? couldn't you degenerate? couldn't she degenerate? couldn't we degenerate? couldn't you degenerate? couldn't they degenerate?
V-ing form
couldn't I be degenerating? couldn't you be degenerating? couldn't she be degenerating? couldn't we be degenerating? couldn't you be degenerating? couldn't they be degenerating?
Perfect
couldn't I have degenerated? couldn't you have degenerated? couldn't she have degenerated? couldn't we have degenerated? couldn't you have degenerated? couldn't they have degenerated?
V-ing perfect
couldn't I have been degenerating? couldn't you have been degenerating? couldn't she have been degenerating? couldn't we have been degenerating? couldn't you have been degenerating? couldn't they have been degenerating?