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 couldn't preach you couldn't preach he couldn't preach we couldn't preach you couldn't preach they couldn't preach
V-ing form
I couldn't be preaching you couldn't be preaching he couldn't be preaching we couldn't be preaching you couldn't be preaching they couldn't be preaching
Perfect
I couldn't have preached you couldn't have preached he couldn't have preached we couldn't have preached you couldn't have preached they couldn't have preached
V-ing perfect
I couldn't have been preaching you couldn't have been preaching he couldn't have been preaching we couldn't have been preaching you couldn't have been preaching they couldn't 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
couldn't I preach? couldn't you preach? couldn't he preach? couldn't we preach? couldn't you preach? couldn't they preach?
V-ing form
couldn't I be preaching? couldn't you be preaching? couldn't he be preaching? couldn't we be preaching? couldn't you be preaching? couldn't they be preaching?
Perfect
couldn't I have preached? couldn't you have preached? couldn't he have preached? couldn't we have preached? couldn't you have preached? couldn't they have preached?
V-ing perfect
couldn't I have been preaching? couldn't you have been preaching? couldn't he have been preaching? couldn't we have been preaching? couldn't you have been preaching? couldn't they have been preaching?