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