I could photograph you could photograph she could photograph we could photograph you could photograph they could photograph
V-ing form
I could be photographing you could be photographing she could be photographing we could be photographing you could be photographing they could be photographing
Perfect
I could have photographed you could have photographed she could have photographed we could have photographed you could have photographed they could have photographed
V-ing perfect
I could have been photographing you could have been photographing she could have been photographing we could have been photographing you could have been photographing they could have been photographing
Negation
Simple form
I couldn't photograph you couldn't photograph she couldn't photograph we couldn't photograph you couldn't photograph they couldn't photograph
V-ing form
I couldn't be photographing you couldn't be photographing she couldn't be photographing we couldn't be photographing you couldn't be photographing they couldn't be photographing
Perfect
I couldn't have photographed you couldn't have photographed she couldn't have photographed we couldn't have photographed you couldn't have photographed they couldn't have photographed
V-ing perfect
I couldn't have been photographing you couldn't have been photographing she couldn't have been photographing we couldn't have been photographing you couldn't have been photographing they couldn't have been photographing
Interrogative form
Simple form
could I photograph? could you photograph? could she photograph? could we photograph? could you photograph? could they photograph?
V-ing form
could I be photographing? could you be photographing? could she be photographing? could we be photographing? could you be photographing? could they be photographing?
Perfect
could I have photographed? could you have photographed? could she have photographed? could we have photographed? could you have photographed? could they have photographed?
V-ing perfect
could I have been photographing? could you have been photographing? could she have been photographing? could we have been photographing? could you have been photographing? could they have been photographing?
Interro-negative form
Simple form
couldn't I photograph? couldn't you photograph? couldn't she photograph? couldn't we photograph? couldn't you photograph? couldn't they photograph?
V-ing form
couldn't I be photographing? couldn't you be photographing? couldn't she be photographing? couldn't we be photographing? couldn't you be photographing? couldn't they be photographing?
Perfect
couldn't I have photographed? couldn't you have photographed? couldn't she have photographed? couldn't we have photographed? couldn't you have photographed? couldn't they have photographed?
V-ing perfect
couldn't I have been photographing? couldn't you have been photographing? couldn't she have been photographing? couldn't we have been photographing? couldn't you have been photographing? couldn't they have been photographing?