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