I could stick you could stick he could stick we could stick you could stick they could stick
V-ing form
I could be sticking you could be sticking he could be sticking we could be sticking you could be sticking they could be sticking
Perfect
I could have stuck you could have stuck he could have stuck we could have stuck you could have stuck they could have stuck
V-ing perfect
I could have been sticking you could have been sticking he could have been sticking we could have been sticking you could have been sticking they could have been sticking
Negation
Simple form
I could not stick you could not stick he could not stick we could not stick you could not stick they could not stick
V-ing form
I could not be sticking you could not be sticking he could not be sticking we could not be sticking you could not be sticking they could not be sticking
Perfect
I could not have stuck you could not have stuck he could not have stuck we could not have stuck you could not have stuck they could not have stuck
V-ing perfect
I could not have been sticking you could not have been sticking he could not have been sticking we could not have been sticking you could not have been sticking they could not have been sticking
Interrogative form
Simple form
could I stick? could you stick? could he stick? could we stick? could you stick? could they stick?
V-ing form
could I be sticking? could you be sticking? could he be sticking? could we be sticking? could you be sticking? could they be sticking?
Perfect
could I have stuck? could you have stuck? could he have stuck? could we have stuck? could you have stuck? could they have stuck?
V-ing perfect
could I have been sticking? could you have been sticking? could he have been sticking? could we have been sticking? could you have been sticking? could they have been sticking?
Interro-negative form
Simple form
could I not stick? could you not stick? could he not stick? could we not stick? could you not stick? could they not stick?
V-ing form
could I not be sticking? could you not be sticking? could he not be sticking? could we not be sticking? could you not be sticking? could they not be sticking?
Perfect
could I not have stuck? could you not have stuck? could he not have stuck? could we not have stuck? could you not have stuck? could they not have stuck?
V-ing perfect
could I not have been sticking? could you not have been sticking? could he not have been sticking? could we not have been sticking? could you not have been sticking? could they not have been sticking?