English verb conjugation
MUST HARKEN

Regular verb: harken - harkened - harkened

Affirmation

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

Negation

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

Interrogative form

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

Interro-negative form

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