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