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 mustn't slacken you mustn't slacken he mustn't slacken we mustn't slacken you mustn't slacken they mustn't slacken	I mustn't be slackening you mustn't be slackening he mustn't be slackening we mustn't be slackening you mustn't be slackening they mustn't be slackening
Perfect	V-ing perfect
I mustn't have slackened you mustn't have slackened he mustn't have slackened we mustn't have slackened you mustn't have slackened they mustn't have slackened	I mustn't have been slackening you mustn't have been slackening he mustn't have been slackening we mustn't have been slackening you mustn't have been slackening they mustn't 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
mustn't I slacken? mustn't you slacken? mustn't he slacken? mustn't we slacken? mustn't you slacken? mustn't they slacken?	mustn't I be slackening? mustn't you be slackening? mustn't he be slackening? mustn't we be slackening? mustn't you be slackening? mustn't they be slackening?
Perfect	V-ing perfect
mustn't I have slackened? mustn't you have slackened? mustn't he have slackened? mustn't we have slackened? mustn't you have slackened? mustn't they have slackened?	mustn't I have been slackening? mustn't you have been slackening? mustn't he have been slackening? mustn't we have been slackening? mustn't you have been slackening? mustn't they have been slackening?