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