English verb conjugation
MUST SLACKEN

Regular verb: slacken - slackened - slackened

Affirmation

Simple form	V-ing form
I must slacken you must slacken he must slacken we must slacken you must slacken they must slacken	I must be slackening you must be slackening he must be slackening we must be slackening you must be slackening they must be slackening
Perfect	V-ing perfect
I must have slackened you must have slackened he must have slackened we must have slackened you must have slackened they must have slackened	I must have been slackening you must have been slackening he must have been slackening we must have been slackening you must have been slackening they must have been slackening

Negation

Simple form	V-ing form
I must not slacken you must not slacken he must not slacken we must not slacken you must not slacken they must not slacken	I must not be slackening you must not be slackening he must not be slackening we must not be slackening you must not be slackening they must not be slackening
Perfect	V-ing perfect
I must not have slackened you must not have slackened he must not have slackened we must not have slackened you must not have slackened they must not have slackened	I must not have been slackening you must not have been slackening he must not have been slackening we must not have been slackening you must not have been slackening they must not have been slackening

Interrogative form

Simple form	V-ing form
must I slacken? must you slacken? must he slacken? must we slacken? must you slacken? must they slacken?	must I be slackening? must you be slackening? must he be slackening? must we be slackening? must you be slackening? must they be slackening?
Perfect	V-ing perfect
must I have slackened? must you have slackened? must he have slackened? must we have slackened? must you have slackened? must they have slackened?	must I have been slackening? must you have been slackening? must he have been slackening? must we have been slackening? must you have been slackening? must they have been slackening?

Interro-negative form

Simple form	V-ing form
must I not slacken? must you not slacken? must he not slacken? must we not slacken? must you not slacken? must they not slacken?	must I not be slackening? must you not be slackening? must he not be slackening? must we not be slackening? must you not be slackening? must they not be slackening?
Perfect	V-ing perfect
must I not have slackened? must you not have slackened? must he not have slackened? must we not have slackened? must you not have slackened? must they not have slackened?	must I not have been slackening? must you not have been slackening? must he not have been slackening? must we not have been slackening? must you not have been slackening? must they not have been slackening?