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