I could compete you could compete he could compete we could compete you could compete they could compete
V-ing form
I could be competing you could be competing he could be competing we could be competing you could be competing they could be competing
Perfect
I could have competed you could have competed he could have competed we could have competed you could have competed they could have competed
V-ing perfect
I could have been competing you could have been competing he could have been competing we could have been competing you could have been competing they could have been competing
Negation
Simple form
I could not compete you could not compete he could not compete we could not compete you could not compete they could not compete
V-ing form
I could not be competing you could not be competing he could not be competing we could not be competing you could not be competing they could not be competing
Perfect
I could not have competed you could not have competed he could not have competed we could not have competed you could not have competed they could not have competed
V-ing perfect
I could not have been competing you could not have been competing he could not have been competing we could not have been competing you could not have been competing they could not have been competing
Interrogative form
Simple form
could I compete? could you compete? could he compete? could we compete? could you compete? could they compete?
V-ing form
could I be competing? could you be competing? could he be competing? could we be competing? could you be competing? could they be competing?
Perfect
could I have competed? could you have competed? could he have competed? could we have competed? could you have competed? could they have competed?
V-ing perfect
could I have been competing? could you have been competing? could he have been competing? could we have been competing? could you have been competing? could they have been competing?
Interro-negative form
Simple form
could I not compete? could you not compete? could he not compete? could we not compete? could you not compete? could they not compete?
V-ing form
could I not be competing? could you not be competing? could he not be competing? could we not be competing? could you not be competing? could they not be competing?
Perfect
could I not have competed? could you not have competed? could he not have competed? could we not have competed? could you not have competed? could they not have competed?
V-ing perfect
could I not have been competing? could you not have been competing? could he not have been competing? could we not have been competing? could you not have been competing? could they not have been competing?