I could brood you could brood he could brood we could brood you could brood they could brood
V-ing form
I could be brooding you could be brooding he could be brooding we could be brooding you could be brooding they could be brooding
Perfect
I could have brooded you could have brooded he could have brooded we could have brooded you could have brooded they could have brooded
V-ing perfect
I could have been brooding you could have been brooding he could have been brooding we could have been brooding you could have been brooding they could have been brooding
Negation
Simple form
I couldn't brood you couldn't brood he couldn't brood we couldn't brood you couldn't brood they couldn't brood
V-ing form
I couldn't be brooding you couldn't be brooding he couldn't be brooding we couldn't be brooding you couldn't be brooding they couldn't be brooding
Perfect
I couldn't have brooded you couldn't have brooded he couldn't have brooded we couldn't have brooded you couldn't have brooded they couldn't have brooded
V-ing perfect
I couldn't have been brooding you couldn't have been brooding he couldn't have been brooding we couldn't have been brooding you couldn't have been brooding they couldn't have been brooding
Interrogative form
Simple form
could I brood? could you brood? could he brood? could we brood? could you brood? could they brood?
V-ing form
could I be brooding? could you be brooding? could he be brooding? could we be brooding? could you be brooding? could they be brooding?
Perfect
could I have brooded? could you have brooded? could he have brooded? could we have brooded? could you have brooded? could they have brooded?
V-ing perfect
could I have been brooding? could you have been brooding? could he have been brooding? could we have been brooding? could you have been brooding? could they have been brooding?
Interro-negative form
Simple form
couldn't I brood? couldn't you brood? couldn't he brood? couldn't we brood? couldn't you brood? couldn't they brood?
V-ing form
couldn't I be brooding? couldn't you be brooding? couldn't he be brooding? couldn't we be brooding? couldn't you be brooding? couldn't they be brooding?
Perfect
couldn't I have brooded? couldn't you have brooded? couldn't he have brooded? couldn't we have brooded? couldn't you have brooded? couldn't they have brooded?
V-ing perfect
couldn't I have been brooding? couldn't you have been brooding? couldn't he have been brooding? couldn't we have been brooding? couldn't you have been brooding? couldn't they have been brooding?