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