English verb conjugation
CAN HARKEN

Regular verb: harken - harkened - harkened

Affirmation

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

Negation

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

Interrogative form

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

Interro-negative form

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