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