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