English verb conjugation
COULD PHOTOGRAPH

Regular verb: photograph - photographed - photographed

Affirmation

Simple form	V-ing form
I could photograph you could photograph he could photograph we could photograph you could photograph they could photograph	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	V-ing 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	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	V-ing form
I couldn't photograph you couldn't photograph he couldn't photograph we couldn't photograph you couldn't photograph they couldn't photograph	I couldn't be photographing you couldn't be photographing he couldn't be photographing we couldn't be photographing you couldn't be photographing they couldn't be photographing
Perfect	V-ing perfect
I couldn't have photographed you couldn't have photographed he couldn't have photographed we couldn't have photographed you couldn't have photographed they couldn't have photographed	I couldn't have been photographing you couldn't have been photographing he 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	V-ing form
could I photograph? could you photograph? could he photograph? could we photograph? could you photograph? could they photograph?	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	V-ing 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?	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	V-ing form
couldn't I photograph? couldn't you photograph? couldn't he photograph? couldn't we photograph? couldn't you photograph? couldn't they photograph?	couldn't I be photographing? couldn't you be photographing? couldn't he be photographing? couldn't we be photographing? couldn't you be photographing? couldn't they be photographing?
Perfect	V-ing perfect
couldn't I have photographed? couldn't you have photographed? couldn't he have photographed? couldn't we have photographed? couldn't you have photographed? couldn't they have photographed?	couldn't I have been photographing? couldn't you have been photographing? couldn't he have been photographing? couldn't we have been photographing? couldn't you have been photographing? couldn't they have been photographing?