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