I could supervise you could supervise he could supervise we could supervise you could supervise they could supervise
V-ing form
I could be supervising you could be supervising he could be supervising we could be supervising you could be supervising they could be supervising
Perfect
I could have supervised you could have supervised he could have supervised we could have supervised you could have supervised they could have supervised
V-ing perfect
I could have been supervising you could have been supervising he could have been supervising we could have been supervising you could have been supervising they could have been supervising
Negation
Simple form
I could not supervise you could not supervise he could not supervise we could not supervise you could not supervise they could not supervise
V-ing form
I could not be supervising you could not be supervising he could not be supervising we could not be supervising you could not be supervising they could not be supervising
Perfect
I could not have supervised you could not have supervised he could not have supervised we could not have supervised you could not have supervised they could not have supervised
V-ing perfect
I could not have been supervising you could not have been supervising he could not have been supervising we could not have been supervising you could not have been supervising they could not have been supervising
Interrogative form
Simple form
could I supervise? could you supervise? could he supervise? could we supervise? could you supervise? could they supervise?
V-ing form
could I be supervising? could you be supervising? could he be supervising? could we be supervising? could you be supervising? could they be supervising?
Perfect
could I have supervised? could you have supervised? could he have supervised? could we have supervised? could you have supervised? could they have supervised?
V-ing perfect
could I have been supervising? could you have been supervising? could he have been supervising? could we have been supervising? could you have been supervising? could they have been supervising?
Interro-negative form
Simple form
could I not supervise? could you not supervise? could he not supervise? could we not supervise? could you not supervise? could they not supervise?
V-ing form
could I not be supervising? could you not be supervising? could he not be supervising? could we not be supervising? could you not be supervising? could they not be supervising?
Perfect
could I not have supervised? could you not have supervised? could he not have supervised? could we not have supervised? could you not have supervised? could they not have supervised?
V-ing perfect
could I not have been supervising? could you not have been supervising? could he not have been supervising? could we not have been supervising? could you not have been supervising? could they not have been supervising?