I could accomplish you could accomplish he could accomplish we could accomplish you could accomplish they could accomplish
V-ing form
I could be accomplishing you could be accomplishing he could be accomplishing we could be accomplishing you could be accomplishing they could be accomplishing
Perfect
I could have accomplished you could have accomplished he could have accomplished we could have accomplished you could have accomplished they could have accomplished
V-ing perfect
I could have been accomplishing you could have been accomplishing he could have been accomplishing we could have been accomplishing you could have been accomplishing they could have been accomplishing
Negation
Simple form
I could not accomplish you could not accomplish he could not accomplish we could not accomplish you could not accomplish they could not accomplish
V-ing form
I could not be accomplishing you could not be accomplishing he could not be accomplishing we could not be accomplishing you could not be accomplishing they could not be accomplishing
Perfect
I could not have accomplished you could not have accomplished he could not have accomplished we could not have accomplished you could not have accomplished they could not have accomplished
V-ing perfect
I could not have been accomplishing you could not have been accomplishing he could not have been accomplishing we could not have been accomplishing you could not have been accomplishing they could not have been accomplishing
Interrogative form
Simple form
could I accomplish? could you accomplish? could he accomplish? could we accomplish? could you accomplish? could they accomplish?
V-ing form
could I be accomplishing? could you be accomplishing? could he be accomplishing? could we be accomplishing? could you be accomplishing? could they be accomplishing?
Perfect
could I have accomplished? could you have accomplished? could he have accomplished? could we have accomplished? could you have accomplished? could they have accomplished?
V-ing perfect
could I have been accomplishing? could you have been accomplishing? could he have been accomplishing? could we have been accomplishing? could you have been accomplishing? could they have been accomplishing?
Interro-negative form
Simple form
could I not accomplish? could you not accomplish? could he not accomplish? could we not accomplish? could you not accomplish? could they not accomplish?
V-ing form
could I not be accomplishing? could you not be accomplishing? could he not be accomplishing? could we not be accomplishing? could you not be accomplishing? could they not be accomplishing?
Perfect
could I not have accomplished? could you not have accomplished? could he not have accomplished? could we not have accomplished? could you not have accomplished? could they not have accomplished?
V-ing perfect
could I not have been accomplishing? could you not have been accomplishing? could he not have been accomplishing? could we not have been accomplishing? could you not have been accomplishing? could they not have been accomplishing?