I could butcher you could butcher he could butcher we could butcher you could butcher they could butcher
V-ing form
I could be butchering you could be butchering he could be butchering we could be butchering you could be butchering they could be butchering
Perfect
I could have butchered you could have butchered he could have butchered we could have butchered you could have butchered they could have butchered
V-ing perfect
I could have been butchering you could have been butchering he could have been butchering we could have been butchering you could have been butchering they could have been butchering
Negation
Simple form
I couldn't butcher you couldn't butcher he couldn't butcher we couldn't butcher you couldn't butcher they couldn't butcher
V-ing form
I couldn't be butchering you couldn't be butchering he couldn't be butchering we couldn't be butchering you couldn't be butchering they couldn't be butchering
Perfect
I couldn't have butchered you couldn't have butchered he couldn't have butchered we couldn't have butchered you couldn't have butchered they couldn't have butchered
V-ing perfect
I couldn't have been butchering you couldn't have been butchering he couldn't have been butchering we couldn't have been butchering you couldn't have been butchering they couldn't have been butchering
Interrogative form
Simple form
could I butcher? could you butcher? could he butcher? could we butcher? could you butcher? could they butcher?
V-ing form
could I be butchering? could you be butchering? could he be butchering? could we be butchering? could you be butchering? could they be butchering?
Perfect
could I have butchered? could you have butchered? could he have butchered? could we have butchered? could you have butchered? could they have butchered?
V-ing perfect
could I have been butchering? could you have been butchering? could he have been butchering? could we have been butchering? could you have been butchering? could they have been butchering?
Interro-negative form
Simple form
couldn't I butcher? couldn't you butcher? couldn't he butcher? couldn't we butcher? couldn't you butcher? couldn't they butcher?
V-ing form
couldn't I be butchering? couldn't you be butchering? couldn't he be butchering? couldn't we be butchering? couldn't you be butchering? couldn't they be butchering?
Perfect
couldn't I have butchered? couldn't you have butchered? couldn't he have butchered? couldn't we have butchered? couldn't you have butchered? couldn't they have butchered?
V-ing perfect
couldn't I have been butchering? couldn't you have been butchering? couldn't he have been butchering? couldn't we have been butchering? couldn't you have been butchering? couldn't they have been butchering?