I could bank you could bank he could bank we could bank you could bank they could bank
V-ing form
I could be banking you could be banking he could be banking we could be banking you could be banking they could be banking
Perfect
I could have banked you could have banked he could have banked we could have banked you could have banked they could have banked
V-ing perfect
I could have been banking you could have been banking he could have been banking we could have been banking you could have been banking they could have been banking
Negation
Simple form
I could not bank you could not bank he could not bank we could not bank you could not bank they could not bank
V-ing form
I could not be banking you could not be banking he could not be banking we could not be banking you could not be banking they could not be banking
Perfect
I could not have banked you could not have banked he could not have banked we could not have banked you could not have banked they could not have banked
V-ing perfect
I could not have been banking you could not have been banking he could not have been banking we could not have been banking you could not have been banking they could not have been banking
Interrogative form
Simple form
could I bank? could you bank? could he bank? could we bank? could you bank? could they bank?
V-ing form
could I be banking? could you be banking? could he be banking? could we be banking? could you be banking? could they be banking?
Perfect
could I have banked? could you have banked? could he have banked? could we have banked? could you have banked? could they have banked?
V-ing perfect
could I have been banking? could you have been banking? could he have been banking? could we have been banking? could you have been banking? could they have been banking?
Interro-negative form
Simple form
could I not bank? could you not bank? could he not bank? could we not bank? could you not bank? could they not bank?
V-ing form
could I not be banking? could you not be banking? could he not be banking? could we not be banking? could you not be banking? could they not be banking?
Perfect
could I not have banked? could you not have banked? could he not have banked? could we not have banked? could you not have banked? could they not have banked?
V-ing perfect
could I not have been banking? could you not have been banking? could he not have been banking? could we not have been banking? could you not have been banking? could they not have been banking?