English verb conjugation
COULD HARKEN

Regular verb: harken - harkened - harkened

Affirmation

Simple form	V-ing form
I could harken you could harken he could harken we could harken you could harken they could harken	I could be harkening you could be harkening he could be harkening we could be harkening you could be harkening they could be harkening
Perfect	V-ing perfect
I could have harkened you could have harkened he could have harkened we could have harkened you could have harkened they could have harkened	I could have been harkening you could have been harkening he could have been harkening we could have been harkening you could have been harkening they could have been harkening

Negation

Simple form	V-ing form
I could not harken you could not harken he could not harken we could not harken you could not harken they could not harken	I could not be harkening you could not be harkening he could not be harkening we could not be harkening you could not be harkening they could not be harkening
Perfect	V-ing perfect
I could not have harkened you could not have harkened he could not have harkened we could not have harkened you could not have harkened they could not have harkened	I could not have been harkening you could not have been harkening he could not have been harkening we could not have been harkening you could not have been harkening they could not have been harkening

Interrogative form

Simple form	V-ing form
could I harken? could you harken? could he harken? could we harken? could you harken? could they harken?	could I be harkening? could you be harkening? could he be harkening? could we be harkening? could you be harkening? could they be harkening?
Perfect	V-ing perfect
could I have harkened? could you have harkened? could he have harkened? could we have harkened? could you have harkened? could they have harkened?	could I have been harkening? could you have been harkening? could he have been harkening? could we have been harkening? could you have been harkening? could they have been harkening?

Interro-negative form

Simple form	V-ing form
could I not harken? could you not harken? could he not harken? could we not harken? could you not harken? could they not harken?	could I not be harkening? could you not be harkening? could he not be harkening? could we not be harkening? could you not be harkening? could they not be harkening?
Perfect	V-ing perfect
could I not have harkened? could you not have harkened? could he not have harkened? could we not have harkened? could you not have harkened? could they not have harkened?	could I not have been harkening? could you not have been harkening? could he not have been harkening? could we not have been harkening? could you not have been harkening? could they not have been harkening?