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