I could roll you could roll she could roll we could roll you could roll they could roll
V-ing form
I could be rolling you could be rolling she could be rolling we could be rolling you could be rolling they could be rolling
Perfect
I could have rolled you could have rolled she could have rolled we could have rolled you could have rolled they could have rolled
V-ing perfect
I could have been rolling you could have been rolling she could have been rolling we could have been rolling you could have been rolling they could have been rolling
Negation
Simple form
I couldn't roll you couldn't roll she couldn't roll we couldn't roll you couldn't roll they couldn't roll
V-ing form
I couldn't be rolling you couldn't be rolling she couldn't be rolling we couldn't be rolling you couldn't be rolling they couldn't be rolling
Perfect
I couldn't have rolled you couldn't have rolled she couldn't have rolled we couldn't have rolled you couldn't have rolled they couldn't have rolled
V-ing perfect
I couldn't have been rolling you couldn't have been rolling she couldn't have been rolling we couldn't have been rolling you couldn't have been rolling they couldn't have been rolling
Interrogative form
Simple form
could I roll? could you roll? could she roll? could we roll? could you roll? could they roll?
V-ing form
could I be rolling? could you be rolling? could she be rolling? could we be rolling? could you be rolling? could they be rolling?
Perfect
could I have rolled? could you have rolled? could she have rolled? could we have rolled? could you have rolled? could they have rolled?
V-ing perfect
could I have been rolling? could you have been rolling? could she have been rolling? could we have been rolling? could you have been rolling? could they have been rolling?
Interro-negative form
Simple form
couldn't I roll? couldn't you roll? couldn't she roll? couldn't we roll? couldn't you roll? couldn't they roll?
V-ing form
couldn't I be rolling? couldn't you be rolling? couldn't she be rolling? couldn't we be rolling? couldn't you be rolling? couldn't they be rolling?
Perfect
couldn't I have rolled? couldn't you have rolled? couldn't she have rolled? couldn't we have rolled? couldn't you have rolled? couldn't they have rolled?
V-ing perfect
couldn't I have been rolling? couldn't you have been rolling? couldn't she have been rolling? couldn't we have been rolling? couldn't you have been rolling? couldn't they have been rolling?