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