I could photograph you could photograph he could photograph we could photograph you could photograph they could photograph
V-ing form
I could be photographing you could be photographing he could be photographing we could be photographing you could be photographing they could be photographing
Perfect
I could have photographed you could have photographed he 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 he could have been photographing we could have been photographing you could have been photographing they could have been photographing
Negation
Simple form
I could not photograph you could not photograph he could not photograph we could not photograph you could not photograph they could not photograph
V-ing form
I could not be photographing you could not be photographing he could not be photographing we could not be photographing you could not be photographing they could not be photographing
Perfect
I could not have photographed you could not have photographed he could not have photographed we could not have photographed you could not have photographed they could not have photographed
V-ing perfect
I could not have been photographing you could not have been photographing he could not have been photographing we could not have been photographing you could not have been photographing they could not have been photographing
Interrogative form
Simple form
could I photograph? could you photograph? could he photograph? could we photograph? could you photograph? could they photograph?
V-ing form
could I be photographing? could you be photographing? could he be photographing? could we be photographing? could you be photographing? could they be photographing?
Perfect
could I have photographed? could you have photographed? could he 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 he have been photographing? could we have been photographing? could you have been photographing? could they have been photographing?
Interro-negative form
Simple form
could I not photograph? could you not photograph? could he not photograph? could we not photograph? could you not photograph? could they not photograph?
V-ing form
could I not be photographing? could you not be photographing? could he not be photographing? could we not be photographing? could you not be photographing? could they not be photographing?
Perfect
could I not have photographed? could you not have photographed? could he not have photographed? could we not have photographed? could you not have photographed? could they not have photographed?
V-ing perfect
could I not have been photographing? could you not have been photographing? could he not have been photographing? could we not have been photographing? could you not have been photographing? could they not have been photographing?